261 FXUS62 KFFC 181003 AFDFFC Area Forecast Discussion National Weather Service Peachtree City GA 603 AM EDT Mon May 18 2026 ...New 12Z Aviation Discussion... .KEY MESSAGES... - A few scattered thunderstorms are possible this afternoon along the GA/AL border, but coverage will be much less than yesterday. - Warmer temperatures the next few days with highs in the upper 80s to low 90s. - Increased rain chances return from Wednesday into next weekend. && .SHORT TERM... (Today through Tuesday) Issued at 500 AM EDT Mon May 18 2026 Another warm day expected this afternoon as temperatures rise into the upper 80s and low 90s. The best chance for afternoon thunderstorms has shifted to the west, though a few isolated thunderstorms are possible along the GA/AL border this afternoon. Coverage seems to be significantly less than yesterdays storms. Instability will be a limiting factor as well with high pressure keeping a cap on most of the CWA. The forecast for Tuesday is a bit of a carbon copy for today though with increasing afternoon clouds out a head of the cold front that's expected to bring the next round of weather. You can find more information about that system in the long term below. Winds will remain southerly at 5-10mph with some higher gusts in the higher elevations of northern Georgia. Overnight lows will be pleasantly in the mid 60s. && .LONG TERM... (Tuesday night through Sunday) Issued at 500 AM EDT Mon May 18 2026 By Wednesday afternoon and evening, a cold front will push southeastward toward far north Georgia. The highest PoPs will be relegated to these areas in proximity to the frontal forcing with drier conditions initially favored farther southeast. The front makes only limited southward progress by Thursday into north Georgia as upper support departs northeastward from the Great Lakes into Quebec. As such, diurnally-enhanced PoPs should again be highest along/north of the I-20 corridor. Flow aloft then transitions into southwest flow by late week as the front becomes stationary. Weak shortwaves within this flow will enhance convective coverage headed into the weekend, particularly with the aid of diurnal heating. Coverage again will likely be highest across roughly the northern half of the area through this period. The organized severe threat continues to look low given the summer-like weakly sheared environment, a couple of strong to isolated severe storms certainly can't be ruled out. While locally heavy rainfall will also be possible, the lack of a widespread and persistent soaking rainfall will limit the overall impact on the drought through the forecast period. Temperatures remain generally several degrees above normal (highs in the mid to upper 80s to lower 90s on the warmest days and lows in the 60s), though marginally cooler highs are possible late week given increased clouds and convective coverage. && .AVIATION... (12Z TAFS) Issued at 602 AM EDT Mon May 18 2026 A low chance for IFR CIGS will linger this morning until 15Z. A CU field with SCT low VFR will form after 15Z with SE winds at less than 10kts. After 00Z, CIGS will return to FEW250. //ATL Confidence...12Z Update... Low on IFR Cigs. High on all elements. Vaughn && .PRELIMINARY POINT TEMPS/POPS... Athens 90 63 89 65 / 0 0 0 0 Atlanta 88 67 88 68 / 0 0 0 0 Blairsville 83 60 83 62 / 10 0 0 0 Cartersville 89 65 89 65 / 10 0 0 10 Columbus 90 66 90 68 / 0 0 0 0 Gainesville 87 63 87 66 / 0 0 0 0 Macon 90 63 90 66 / 0 0 0 0 Rome 88 63 88 63 / 20 0 0 10 Peachtree City 89 64 89 65 / 0 0 0 0 Vidalia 90 64 91 65 / 0 0 10 0 && .FFC WATCHES/WARNINGS/ADVISORIES... None. && $$ SHORT TERM...Vaughn LONG TERM....Vaughn AVIATION...Vaughn  396 FXUS63 KIWX 181006 AFDIWX Area Forecast Discussion National Weather Service Northern Indiana 606 AM EDT Mon May 18 2026 .KEY MESSAGES... - Strong to severe storms are likely today between 12 PM to 8 PM EDT. Damaging wind gusts to 60 mph and heavy rain are the main threats. Low but non-zero risk for large hail and an isolated tornado. - Strong to severe storms are anticipated again Tuesday afternoon and evening, with all hazards possible. - Warm and humid through Tuesday with highs in the mid to upper 80s. - Cooler with seasonable temperatures and dry midweek. Highs only in the 60s Wednesday and Thursday. && .DISCUSSION... Issued at 316 AM EDT Mon May 18 2026 Satellite and radar imagery currently shows a line of strong to severe thunderstorms persisting across parts of Iowa and Missouri. This activity is expected to weaken as it moves east into Illinois before daybreak. As an upper level trough digs across the Four Corners region on today, an impressive and expansive Gulf connection will strengthen, sending even stronger surges of moisture and warmth into the Upper Great Lakes region. Dewpoints will increase to the upper 60s to near 70 degrees in response. A prefrontal trough and several 500mb shortwaves will provide a source of lift as storms from Illinois are likely to reintensify as they move into our forecast area around midday. SPC maintains a Slight Risk (level 2 of 5) for much of our forecast area. With highs in the mid to upper 80s again today, the atmosphere will be unstable with 1500-2000 J/kg of SBCAPE and steep low level lapse rates as high as 8 C/km. The greatest instability and lapse rates will be along and east of IN- 15, as these areas will have the longest to destabilize before storms come through. Despite a lack of organized bulk shear (only ~20 kts), forecast soundings depict a favorable environment for damaging winds with inverted v soundings and DCAPE around 1000 J/kg. Cannot rule out hail or an isolated tornado from any discrete storms that develop ahead of the line. With PWATs around 1.25-1.5", even if storms are not severe, they will likely be efficient with rainfall rates in excess of 1"/hr. Our forecast area will be in a favorable region for severe weather again on Tuesday afternoon and evening ahead of an incoming cold front. SPC once again has a Slight Risk (level 2 of 5) for much of our forecast area. The environment will be very similar to Monday with highs in the mid to upper 80s and dewpoints in the upper 60s. This will boost SBCAPE to 1500-2000 J/kg during peak heating hours. With the cold front as the source of lift, forecast soundings depict slightly better shear of 30 kts and 0-1 SRH up to 200 m2/s2. At this point, all hazards are possible, but damaging winds appear to be the main threat. There is some veering present in the lowest 1km per forecast soundings, but then the vertical wind profile is unidirectional above 1 km. Given low level clockwise turning of winds with height and LCLs below 1000m, I can't rule out isolated tornadoes occuring Tuesday ahead of the cold front. It will be noticeably drier with much more seasonable conditions midweek behind the cold front. High pressure builds in on Wednesday and Thursday across the Great Lakes region. Highs will be in the 60s and it will feel much cooler than the previous stretch of warm and humid days. Summer-like temperatures return next week with additional chances for rain/storms. && .AVIATION /12Z TAFS THROUGH 12Z TUESDAY/... Issued at 604 AM EDT Mon May 18 2026 Minimal changes made to the 12Z TAFs. VFR conditions will continue through midday. A decaying MCS out of Iowa and Missouri has produced an outflow boundary in Illinois and storms are forming along it. This complex of developing storms is expected to weaken over Illinois this morning and then reintensify over northern Indiana around 18Z becoming strong to severe. Breezy southerly winds will gust as high as 30 kts today, even outside of any showers or storms. The strongest storms may end up east of IN-15 towards KFWA, but have maintained a PROB30 at KSBN for 17-20Z and a few hours later at KFWA from 19-22Z. MVFR ceilings and visibilities possible within any storms. The main threats today will be heavy rain and damaging wind gusts up to 50kts. && .IWX WATCHES/WARNINGS/ADVISORIES... IN...None. OH...None. MI...None. MARINE...None. && $$ DISCUSSION...Johnson AVIATION...Johnson  476 FXUS63 KIND 181009 AFDIND Area Forecast Discussion National Weather Service Indianapolis IN 609 AM EDT Mon May 18 2026 .KEY MESSAGES... - Severe storms possible this afternoon and again Tuesday afternoon and evening with damaging winds, large hail and localized flooding - Highs in the 80s today and Tuesday - Storms will end Wednesday as the front shifts south, but unsettled weather likely returns late this week into the holiday weekend && .DISCUSSION (Today through Sunday)... Issued at 258 AM EDT Mon May 18 2026 An amplified upper level pattern for early this week anchored by a deep trough over the northern Rockies and strong ridging over the eastern part of the country. The ridge will gradually flatten as the trough shifts east enabling a strong cold front to track into the region by late Tuesday. With a warm and unstable airmass ahead of the front...multiple opportunities for thunderstorms will exist through Tuesday night with severe weather possible this afternoon and potentially again Tuesday afternoon and evening as the cold front moves through. High pressure will bring a briefly drier period midweek before unsettled conditions return late week in response to the front lifting back north into the region. Today through Tuesday Night Quiet early morning across central Indiana with clear skies. 06Z temperatures remained warm in the upper 60s and lower 70s in many locations. An active 48 hours is anticipated through Tuesday night with multiple opportunities for rain and thunderstorms and the potential for severe weather in advance of a cold front currently over the Plains and poised to move across the area by Tuesday evening. An ongoing area of convection continues early this morning from the upper Midwest southwest into central Kansas. Much of the line has weakened from Sunday evening with the exception of the southern part of the line over the Missouri Valley where instability and BL shear remain more than sufficient to maintain convective intensity. This portion of the line is likely to remain strong for the remainder of the night with an in creasing flood risk as it sags into south central Missouri and becomes increasingly parallel to the mean flow. The weaker portion of the line over Iowa is of greater interest to the forecast area as its remnants will enable the old outflow boundary to drift into central Illinois by mid to late morning with convection becoming reinvigorated as the outflow interacts with a rapidly destabilizing airmass over the region. Convection will continue to grow upscale as it tracks into the Wabash Valley early this afternoon then presses southeast across the forecast area. Model soundings show steepening mid level lapse rates with SBCAPEs 2000-2500 j/kg and sufficient shear that would support damaging winds...especially if the cold pool can mature. Furthermore...DCAPE values approach 1000 j/kg immediately ahead of the convective line which also lends credence to the damaging wind risk. Abundant CAPE is present within the hail growth zone as well and stronger cells will carry a large hail threat as well. Timing of the greatest risk for severe weather will be between 17Z and 22Z. Storms will weaken as they track towards the Indiana-Ohio border by early evening as it moves away from the deeper instability and stronger low level winds. An axis of PWATs between 1.75 and 2 inches will support torrential rainfall and flooding. The greatest concern will be across the southwest half of the forecast area as training cells become a factor with the line curving back to the west along the instability axis. Showers and embedded storms will continue into the evening but with the airmass worked over from the afternoon convection...the general trend will be towards rain diminishing as weak ridging aloft reestablishes for the overnight. Tuesday has become a bit more uncertain with respect to convective evolution and the potential for another round of severe weather as the model suite has sped up the arrival of the front into the forecast area in the afternoon. More impactful though will be the possibility of convective cloud debris by Tuesday morning from an MCS over the Missouri Valley Monday night. That will stunt diurnal heating and available instability and the earlier arrival of the front during the afternoon presents the possibility that the greater risk for more robust convection will focus across the southeast half of the forecast area and points east late afternoon into the evening. That being said...model soundings do continue to highlight mid level lapse rates up to 7.5C/km with a deep layer of dry adiabatic flow across the region combined with sufficient levels of BL shear to support scattered stronger convection at a minimum with the available instability. Damaging winds will again be the primary risk from these storms with large hail serving as a secondary threat. The cold front will become more parallel to the flow aloft on Tuesday night which will keep showers and thunderstorms across much of the forecast area into Tuesday night...gradually ending from the north overnight as drier air advects into the region. Highs will be tricky both today and Tuesday...dependent on convective timing this afternoon and cloud debris Tuesday. Nudged highs both days down from the model blend with low to mid 80s for much of the forecast area. Wednesday through Sunday Convection may still be ongoing across the southeast half of the forecast area Wednesday morning but will gradually end through the morning as the front shifts south of the region and high pressure builds into the Great Lakes. Confidence continues to grow on the boundary becomes quasi stationary across the Tennessee Valley into Thursday before lifting back north into the Ohio Valley Friday as the high passing to the north moves east into New England. The ensemble guidance has gotten more aggressive in this solution with scattered to numerous showers and storms Friday and Friday night as the front lifts north through the forecast area. Lower confidence remains for the weekend as the return of a warmer and more unstable airmass south of the front will support at least a daily threat for scattered convection but the lack of much agreement in the model ensemble makes employing detail in the timing and coverage of rainfall difficult through much of the holiday weekend. After temperatures mainly in the upper 60s and low 70s Wednesday and Thursday...highs will climb back into the upper 70s and lower 80s Saturday and Sunday. && .AVIATION (12Z TAF Issuance)... Issued at 609 AM EDT Mon May 18 2026 Impacts: - A line of severe thunderstorms expected to impact all terminals this afternoon with showers continuing into the evening - Peak wind gusts this afternoon at 25 to 30kts Discussion: Mainly sunny skies are expected to start but expect an increase in mid and high level clouds as the morning progresses associated with the remnant convective cluster extending from western Illinois back into Missouri. Storms should continue to weaken over the next few hours but the leftover outflow boundary is likely to serve as a focal point for renewed convective development by late morning across central and eastern Illinois as it interacts with an increasing unstable airmass. The line will move into the Wabash Valley early this afternoon then track across the terminals during the 17 to 22Z timeframe. Damaging winds will be a possibility along the leading edge of the convective line Restrictions to IFR and lower will accompany the line as well. Scattered convection should linger into the evening before gradually diminishing in coverage. Windy conditions will develop quickly after daybreak with peak gusts at 25 to 30kts prior to storms arriving in the afternoon. Gusts should drop off by early evening. && .IND WATCHES/WARNINGS/ADVISORIES...None. && $$ AVIATION...Ryan DISCUSSION...Ryan  068 FXUS61 KAKQ 181013 AFDAKQ AREA FORECAST DISCUSSION National Weather Service Wakefield VA 613 AM EDT Mon May 18 2026 .WHAT HAS CHANGED... Updated discussion. Pushed best rain chances slightly farther back in time Wed night/early Thu. Increased highs slightly for Wednesday into the mid to upper 90s. Heat index values likely remain close to the air temperature. && .KEY MESSAGES... 1) Remaining hot and dry, with well above normal temperatures continuing through Wednesday. Rain chances increase Wednesday night ahead of an approaching cold front. Best rain chances late Wednesday remains over northern portions of the area. 2) An increasingly unsettled and cooler pattern looks to evolve for the late week period with more uncertainty in temperatures over the Memorial Day Weekend. && .DISCUSSION... As of 250 AM EDT Monday... KEY MESSAGE 1...Remaining hot and dry, with well above normal temperatures continuing through Wednesday. Rain chances increase Wednesday night ahead of an approaching cold front. Best rain chances late Wednesday remains over northern portions of the area. Building ridging and minimal low-level moisture should lock in a summer-like heat and continued dry conditions for the first half of the week. Widespread low-mid 90s are expected inland each day, with lower 90s closer to the immediate coast due to H85 temps maxing out between 18-20 deg C, deep mixing, and continued low-level SSW flow. Temps will be similar each day, perhaps increasing a degree or so each day, culminating with the warmest day of the week on Wednesday. The strong mixing and dry antecedent conditions will continue to allow early morning dewpoints to mix out by afternoon, and fall back into the upper 50s to low 60s each day. This will keep heat indices close to actual air temps. The downside to that point is that limited moisture return and downslope flow aloft will also likely maintain dry wx across the region at least into Wed afternoon. By Wednesday afternoon, upper heights begin to fall ahead of a cold front approaching the region from our NW. Showers and storms should develop to our northwest ahead of the boundary by midday Wednesday, focused mainly on the pre-frontal lee trough. Given a gradual slowing trend in recent model guidance, it appears much of the convection most likely stays north and west of the RIC Metro Wed evening. KEY MESSAGE 2...An increasingly unsettled and cooler pattern looks to evolve for the late week period with more uncertainty in temperatures over the Memorial Day Weekend. A shortwave trough is progged to lift across the upper Midwest into eastern Canada Wednesday into Thursday. This will serve to dampen to SE ridge, while also allowing cool high pressure to settle over the Great Lakes and SE Canada. While there remain model differences, the previously referenced cold front looks to slowly drop south across the area on Thursday, then lingers across the area Thu evening before pushing south of the local area Thu night into Friday. With the front moving south of the area, expect a cooler, cloudy day with mainly stratiform rain/drizzle Thu night/Friday, though it is possible the warm sector could linger a bit later into Thu across extreme SE portions of the area, allowing for few rumbles of thunder. Temps may struggle to get out of the lower 60s on Thursday and Friday (especially N/NE) as cool high pressure wedges down into the region. While the Thursday forecast is a bit higher confidence with the front dropping into the region, the temperature forecast on Friday and especially Saturday remains highly uncertain, and depends on the exact position of the front. 00z LREF continues to feature model spread in 2m temperatures of ~12-15 deg F for Friday across much of the area! While some uncertainty lingers into Saturday, especially inland, it does appear as if the wedge airmass erodes quickly, as the parent high exits to the east and the front lifts back north of the local area into the upcoming weekend. Some additional isolated to scattered showers and a few storms (along with warmer temps) are possible Sat/Sun, but by no means does the holiday weekend look to be a washout. Gradual warming is expected as we head into early next week, as mid-level ridging rebuilds east of the Rockies early next week. As for precipitation amounts, ensemble (EPS/GEPS/GEFS) probabilities for at least 0.5" of 48-hour total rainfall for the Wed night-Fri Night period still hover around or just above 50-70% across the entire CWA. However, it is hard to stay as optimistic as ensemble/NBM guidance, given that 1) a potentially unfavorable FROPA timing for convection (Model timing with the front is even later into Wed night/early Thu. Wednesday's convection looks likely to be focused to our NNW, with Thursday's heavier rainfall potentially to be suppressed to our south) and 2) several recent rain events have underperformed with respect to Day 3-5 model/ensemble forecasts. && .AVIATION /10Z MONDAY THROUGH FRIDAY/... As of 615 AM EDT Monday... VFR conditions currently across area terminals look to prevail through the 12z/17 TAF period, as high pressure remains anchored offshore. Aside from some SCT high clouds along the coast this morning, mainly clear/sunny conditions across the area today. Winds remain light ~5-8 kt out of the SSW this morning, backing to the SSE this afternoon 10 kt with occasional gusts to ~15-18 kt. Outlook...VFR conditions expected through midweek, as high pressure remains in control. South/southwest winds each afternoon may gust to 15-20kt each day through Wed. Next chance of rain not expected until late Wed or Thursday. && .MARINE... As of 240 AM EDT Monday... Key Messages: - Mainly Sub-SCA conditions are expected across the local waters through at least mid-week with primarily southerly winds. - A front moves through late week, bringing the next chance at SCA conditions. Expansive high pressure remains parked across the western Atlantic and extends across the Southeast. Winds remain out of the SW at generally 10 to 15 kt across the local waters. Seas are 2-3 ft across the coastal waters and 1 ft or less in the Bay and rivers (1- 2 ft at the mouth of the Bay). Through mid-week, high pressure will remain parked across the western Atlantic in a typical summertime Bermuda High configuration. Winds remain primarily SSW around 10 to 15 kt outside of the daily mid to late-afternoon nearshore seabreeze. The afternoon breeze will likely bring additional localized gusts of 15-20 kt to the lower Chesapeake Bay and nearshore ocean waters each afternoon before winds veer back offshore and diminish through the overnight. These surges will be relatively brief and likely will not require any SCAs. Expect generally benign marine conditions to prevail through at least midweek. The next cold front looks to cross the waters some time early Thursday morning with increasing NE winds late week. At this time, in-house wind probs suggest that even behind the front, only brief marginal SCA conditions are possible and conditions may stay under SCA criteria through next weekend. Whether or not the aforementioned front actually moves through or stalls across the area will play an important role in the wind regime late week into the weekend. && .CLIMATE... As of 145 AM Monday... Record High Temps for 5/18 - 5/20 Record Record Record High/Year High/Year High/Year Location 5/18 5/19 5/20 -------- ---- ----- ------ Richmond 95 (1962) 97 (1962) 97 (2022) Norfolk 95 (1877) 96 (1880) 98 (1996) Salisbury 96 (1911) 97 (2011) 98 (1911) Eliz. City 93 (1987) 95 (1996) 98 (1996) Record High Min Temps for 5/18- 5/20 Record Record Record High High High Min T/Year Min T/Year Min T/Year Location 5/18 5/19 5/20 -------- ---- ----- ------ Richmond 72 (2015) 71 (1997) 71 (2018) Norfolk 75 (1995) 72 (2017) 73 (1996) Salisbury 71 (1953) 70 (1929) 70 (2018) Eliz. City 73 (1995) 72 (2018) 73 (2018) && .AKQ WATCHES/WARNINGS/ADVISORIES... MD...None. NC...None. VA...None. MARINE...None. && $$ DISCUSSION...ERI/MAM AVIATION...AC/MAM MARINE...NB CLIMATE...MAM  173 FXUS64 KFWD 181016 AFDFWD Area Forecast Discussion National Weather Service Fort Worth TX 516 AM CDT Mon May 18 2026 ...New AVIATION... .KEY MESSAGES... - Isolated showers and thunderstorms are possible again today, but most areas will stay dry. - More widespread showers and storms are expected Tuesday and Wednesday as a cold front moves into and stalls across the region. Heavy rainfall and some strong to severe storms are possible both days. - Daily chances for scattered showers and storms will continue the rest of the week into the weekend. Locally heavy rain will be possible but the severe weather threat appears low. && .SHORT TERM... (Today through Tuesday night) Issued at 1220 AM CDT Mon May 18 2026 Latest radar imagery shows the showers and storms that affected North and Central Texas on Sunday evening have moved out of our area into East Texas, with dry conditions now in place. In the wake of this activity, surface obs and area radars show the nocturnal LLJ has kicked into gear early this morning with winds up to 50 knots at 3k ft per the KFWS VAD wind profile. This will lead to gusty south winds up to 40 mph at times throughout the day today and even into tonight. The LLJ is also bringing a surge of low clouds rapidly northward which are expected to blanket most of the area until breaking up by midday, allowing for another warm, humid afternoon with highs in the 80s and 90s. Precip chances for today look quite low as main synoptic features and forcing stay well to our north. Even so, moisture remains plentiful with a PWAT of 1.87 inches on the 00Z FWD sounding, so a few isolated showers or even a thunderstorm could potentially pop up. Much higher rain chances, however, will wait until tomorrow as a cold front moves in from the north. Latest models/CAMs show the front arriving into Montague County in the 12-15Z timeframe Tuesday morning, then reaching the Metroplex around 18-20Z before stalling across Central Texas by 00Z. Majority of guidance shows widespread showers and storms along the front, some of which could be strong to severe with damaging winds and large hail given the high CAPE/weak shear profiles shown on forecast soundings. This activity should diminish from north to south with time Tuesday evening/night. && .LONG TERM... (Wednesday through Sunday) Issued at 1220 AM CDT Mon May 18 2026 Overall pattern with southwesterly flow aloft, frequent embedded shortwaves moving overhead, and stalled/gradually washing out stationary front will remain in place the rest of the week into the weekend. This should lead to fairly high daily rain chances each day, especially across Central Texas. Forecast soundings for the rest of the week show much lower CAPE and continued weak shear, so the severe threat is expected to be low, with the main focus shifting to heavy rain and localized flooding potential. Latest model QPF totals along with WPC show rainfall amounts over the next 7 days ranging from 1 inch in northwest Texas to as much as 5 inches in our southeast counties. Should these rainfall totals pan out, they would put a big dent in the drought conditions across our eastern and southeast counties. && .AVIATION... (12Z TAFS) Issued at 338 AM CDT Mon May 18 2026 MVFR cigs will continue at all airports through 16Z this morning with a return to VFR conditions afterwards. Strong south winds 15-25 kts with gusts 25-35 kts are expected much of the day with highest gusts during the afternoon. Winds will subside somewhat after 01Z with another round of MVFR cigs arriving 06-09Z at all airports. && .SPOTTER INFORMATION STATEMENT... Issued at 1220 AM CDT Mon May 18 2026 Spotter activation is not expected at this time. && .PRELIMINARY POINT TEMPS/POPS... Dallas-Ft. Worth90 74 87 68 / 20 40 80 70 Waco 88 75 87 69 / 10 20 70 70 Paris 87 73 83 66 / 20 30 90 70 Denton 89 75 86 65 / 20 50 90 70 McKinney 89 74 86 66 / 20 40 80 70 Dallas 91 75 88 68 / 20 40 80 70 Terrell 89 73 87 68 / 10 30 80 70 Corsicana 91 76 89 71 / 10 30 80 70 Temple 90 76 89 70 / 10 20 70 70 Mineral Wells 88 73 87 64 / 20 40 90 70 && .FWD WATCHES/WARNINGS/ADVISORIES... None. && $$ SHORT TERM...Shamburger LONG TERM....Shamburger AVIATION...Shamburger  239 FXUS64 KOHX 181017 AFDOHX Area Forecast Discussion National Weather Service Nashville TN 517 AM CDT Mon May 18 2026 ...New AVIATION... .KEY MESSAGES... Updated at 516 AM CDT Mon May 18 2026 - Above normal temperatures in the upper-80s to low-90s continue through Tuesday. - There is a high chance for showers and storms Tuesday night into Wednesday. The severe threat is very low. - Additional rain chances late week may push rainfall totals over 2 inches by the end of the week. && .SHORT TERM... (Tonight through Tuesday Night) Issued at 1021 PM CDT Sun May 17 2026 Southerly flow persists again Monday, allowing for another day of above normal warmth as temperatures make their way into the upper-80s to low-90s again. There is a disturbance to the northwest of Middle TN that will be responsible for afternoon convection. Most of this should stay to our northwest, but CAMs this evening are picking up on an isolated storm or two that may clip the Stewart County area late into Monday evening. Regardless, most of Middle TN will remain dry through Monday. The pattern is still looking favorable for beneficial rain starting on Tuesday. A troughing pattern develops across the eastern CONUS with a series of shortwaves impacting the area through the end of the week, and moisture values will be on the rise with PWATs on Tuesday increasing to around 1.5 inches. As a cold front slowly approaches from the northwest, rain chances will increase ahead of it to around 60-80%, particularly Tuesday afternoon into the night. The severe weather threat for Tuesday looks low with better wind shear displaced to the north, but won't rule out a thunderstorm producing strong winds. && .LONG TERM... (Wednesday through next Monday) Issued at 1021 PM CDT Sun May 17 2026 Highest rain chances of the week are on Wednesday as the front slowly pushes south. Severe weather threat Wednesday still looks to be low as the highest wind shear still is to the north, displaced from the higher instability to the south ahead of the front. But again, won't rule out the low chance for strong to damaging winds due to the front. Then unsettled weather is favored to persist through the end of the week and into next weekend as the front stalls somewhere over the region and southerly flow continues to advect moisture into the area. PWATs are expected to remain high at 1.5" or higher, helping to keep medium to high rain chances in the forecast. Probabilities for beneficial rain continue to trend up with latest ensemble guidance giving a 50-70% chance for at least 2 inches of rain by the end of the week which would certainly be good news for the drought. && .AVIATION... (12Z TAFS) Issued at 516 AM CDT Mon May 18 2026 VFR will continue through this TAF cycle. South winds will be light at night and gusty to 20-25 KTS daytime. && .PRELIMINARY POINT TEMPS/POPS... Nashville 92 71 91 67 / 0 0 30 60 Clarksville 90 72 90 66 / 10 0 50 80 Crossville 85 66 85 63 / 0 0 20 40 Columbia 90 70 90 66 / 0 0 30 60 Cookeville 88 69 87 64 / 0 0 20 50 Jamestown 89 66 88 63 / 10 0 20 40 Lawrenceburg 88 71 87 66 / 0 0 20 50 Murfreesboro 91 71 90 66 / 0 0 20 50 Waverly 90 73 90 67 / 0 0 40 70 && .OHX WATCHES/WARNINGS/ADVISORIES... None. && $$ SHORT TERM...Clements LONG TERM....Clements AVIATION.....13  204 FXUS66 KSEW 181016 AFDSEW Area Forecast Discussion National Weather Service Seattle WA 316 AM PDT Mon May 18 2026 .SYNOPSIS... High pressure will remain situated offshore through much of next week, maintaining near-normal temperatures across western Washington with cloudy mornings and sunshine in the afternoons. A few weak systems will move over the top of the ridge towards the middle of next week, bringing little more than a few periods of sprinkles. && .SHORT TERM /TODAY THROUGH WEDNESDAY/... Upper-troughing currently over the Great Basin while an upper- level ridge is just offshore the PNW. High clouds are currently streaming in under northwest flow aloft. Areas of fog/low stratus are still likely to develop this morning but coverage will be at a minimum. Any fog that should form will give way to sunshine today as the aforementioned ridge centers overhead. High temperatures are forecast in the 60s across the interior with 50s along the coast. Increasing onshore flow will lead to breezy winds through the Strait of Juan de Fuca this evening with gusts up to 30 mph on Whidbey Island before gradually decreasing later tonight. HREF suggests a 35% chance of gusts exceeding 35 mph. Overnight lows will fall into the 40s. Upper-ridging is likely to maintain through midweek as conditions remain rather benign. Weak disturbances will attempt to traverse along the periphery of the ridge - maintaining slight (15% or less) PoPs but mostly for the mountains. Temperatures are to remain near-seasonal throughout this period with highs in the 60s to near lower 70s and lows in the 40s. && .LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/... The upper level ridge offshore will begin to flatten on Thursday as a low pressure system slowly strengthens and lowers from the Gulf of Alaska. Conditions are favored to remain dry into the first half of the weekend as zonal flow sets up aloft, with continued mild temperatures. Ensembles are honing in on a potential pattern change by the end of next weekend, with increasing chances for widespread rainfall arriving Sunday evening. However, the details remain uncertain at this time. 41 && .AVIATION... North/northwesterly winds will persist aloft as an upper level ridge remains nudged over the region. Onshore flow will continue in the low levels, allowing for another round of stratus to push inland this morning, mainly for areas along the coast, the Southwest Interior, and the south Sound. A few isolated spots of patchy fog may also develop across the Chehalis Valley and Kitsap Peninsula early this morning, though high clouds streaming in overhead should help hinder any widespread development. Conditions at the area terminals remain VFR, though could see terminals briefly dip down to MVFR between 12-15Z (most likely for KHQM, KPWT, and KOLM). Expect cigs at the remainder of the terminals to remain VFR through the day. Winds remain light southerly at 6 kt or less across the majority of the interior terminals this morning, outside of KPAE, where winds continue out of the north. Winds along the coast are light northwesterly and KCLM remains westerly between 8-12 kt under increased onshore flow. Winds will increase to 7-10 kt this afternoon and look to switch to the north across the interior between 00-03Z tonight. A weak, splitting frontal system will move into the area tonight into Tuesday, with the main impact being more widespread stratus by Tuesday morning. KSEA...Ceilings look to remain VFR through the day, with a few scattered clouds possible at the terminal between 2000-3000 ft early this morning. The latest probability of ceilings dipping to MVFR is 15 percent this morning. A much greater probability (40-45 percent) exists of ceilings dropping to MVFR by Tuesday morning. Winds are southerly and will increase to 7-10 kt this afternoon, before switching to the north between 00-03Z. 14 && .MARINE... High pressure will remain situated over the northeastern Pacific through much week, bringing a prolonged period of north/northwesterly winds to the coastal waters. A weak, splitting frontal system will move into the waters tonight into Tuesday and will bring an increase of onshore flow along the central and eastern Strait of Juan de Fuca, with another round of small craft westerlies expected this afternoon and evening. High pressure will build back into the coastal waters in the wake of the front. Onshore flow will persist throughout much of the week and will result in daily pushes of westerly winds along the Strait. The next weak frontal system looks to move into the area waters Thursday into Friday, followed by another late next weekend. Seas will generally hover between 6-8 ft through the first half of the week, before increasing towards 8-10 ft mid to late week. The latest GEFS probabilistic guidance is highlighting roughly a 20-40 percent chance of seas exceeding 9 ft by next weekend. 14 && .HYDROLOGY... The daily hydrology discussion has ended until the start of the next rainy season; it will only be updated during this time as needed. && .SEW WATCHES/WARNINGS/ADVISORIES... WA...None. PZ...Small Craft Advisory until 5 AM PDT early this morning for Central U.S. Waters Strait Of Juan De Fuca-East Entrance U.S. Waters Strait Of Juan De Fuca. Small Craft Advisory from 2 PM this afternoon to 5 AM PDT Tuesday for Central U.S. Waters Strait Of Juan De Fuca- East Entrance U.S. Waters Strait Of Juan De Fuca. && $$  287 FXUS61 KPHI 181019 AFDPHI Area Forecast Discussion National Weather Service Mount Holly NJ 619 AM EDT Mon May 18 2026 .WHAT HAS CHANGED... Heat Advisory issued for the PA and NJ urban corridor, in effect today through Tuesday. Added a Climate Section, which includes record high and warmest low temperatures for the area through Wednesday. && .KEY MESSAGES... 1. Unusual and potentially record setting early season heat is expected through Wednesday. High temperatures will generally be upward of 10 to 20 degrees above normal, with low to mid 90s expected for many areas today through Wednesday. 2. A cold front will bring some showers and thunderstorms to the region Wednesday through Thursday, along with moderating temperatures closer to normal by the end of this week. && .DISCUSSION... KEY MESSAGE 1...Unusual and potentially record setting early season heat is expected through Wednesday. High temperatures will generally be upward of 10 to 20 degrees above normal, with low to mid 90s expected for many areas today through Wednesday. An upper level ridge will remain in place across the East Coast through Tuesday then shift offshore and weaken into Wednesday. This will bring a period of well above normal, summer-like temperatures which could challenge monthly all time records for May. At the surface, Bermuda high pressure will remain in place offshore as a low pressure system develops across the Plain, passing across the Great Lakes Tuesday and passing well to our north by Wednesday. This will result in a very warm south to southwesterly flow for several days. The warming trend that began over the weekend will continue into early this week. High temperature for inland areas today will be generally in the upper 80s to mid 90s for eastern PA, inland NJ and Delmarva. However, the flow be more out of the south to even southeast, so there will be more of cooling influence near the coast by the afternoon as the marine layer pushes inland. This cooling will extend a bit farther inland compared to Sunday given the surface flow direction. This will keep highs in these areas near the coast mainly in the mid 70s to mid 80s, occurring around midday before cooling off into the afternoon and evening. Dewpoints should mix out a bit this afternoon due to a lack of deep moisture return, cool ocean temperatures, and low evapotranspiration, but will still be mainly in the low to mid 60s. Not terribly humid, but certainly uncomfortable since we aren't acclimated to it yet. The dewpoint values will translate to heat indices being close to the air temperatures. With temperatures getting into the mid 90s in the urban corridor, we've opted to start the Heat Advisory at noon today, though temperatures and heat indices will likely be hotter on Tuesday (more on that below). Given the likely bay breeze developing in Wilmington today, we've excluded New Castle County from the advisory. Mostly sunny skies today with scattered cirrus around. Can't rule out an isolated shower/storm in our western zones this afternoon, but this potential is low enough that we don't have much in the way of precip mentioned in the forecast. Temperatures tonight will be quite warm by mid May standards. Lows will only be in the mid 60s to low 70s, which will challenge daily warmest low temperature records for May 19th. Confidence continues to increase that Tuesday will be the hottest day across the region. Widespread temperatures in the mid 90s are expected. Even with many of the aforementioned factors keeping heat indicies close to air temperatures will continue into Tuesday, the hotter air temperatures will push heat indicies higher and exceed the early season criteria in the urban areas. Thus, the Heat Advisory will continue through Tuesday evening. The heat forecast remains abit more uncertain for Wednesday, as a faster progression of an approaching front may bring more clouds ahead of the showers and storms, and cap temps and heat indices a bit lower. Regardless, it will still be abnormally warm and keep portions of the area close to record high temperatures, particularly near and southeast of I-95 where skies will remain clear the longest. The heat looks to break by Thursday following the cold frontal passage late Wednesday. Temperatures will moderate closer to normal for the remainder of the week and into next weekend. KEY MESSAGE 2...A cold front will bring some showers and thunderstorms to the region Wednesday through Thursday, along with moderating temperatures closer to normal by the end of this week. As mentioned above, a cold front will approach the area Wednesday and bring an end to the stretch of above normal temperatures by Thursday. Showers and thunderstorms will accompany this front as it passes through the region. Recent guidance trends continue to show the front moving through during the second half of Wednesday into Wednesday night. At this range there is still uncertainties in timing, but if the front moves through during the day Wednesday, then the potential for stronger storms increases as there will be plenty of instability present. Currently, the better forcing looks to be displaced to the north of the front. All of this said, it remains still a bit early to get very specific on the details and extent of the convection, impacts, and hazards. The front then looks to linger nearby or just south of the area on Thursday leading to more potential for showers. By the end of the week and into next weekend, the trend continues to show a more unsettled pattern. && .AVIATION /10Z MONDAY THROUGH FRIDAY/... The following discussion is for KPHL, KPNE, KTTN, KABE, KRDG, KILG, KMIV, KACY and surrounding areas. Today...VFR. S to SW winds near 5 kts in the morning, increasing to around 10 kts by 18Z. Winds a little more east of south for ILG, MIV, and ACY, and perhaps as high as 15 kts at times, but not anticipating any prevailing gusts. High confidence. Tonight...VFR. SSW winds 5-10 kts. High confidence. Outlook... Tuesday...VFR prevailing with no significant weather expected. Wednesday through Thursday...Sub-VFR with rain showers and thunderstorms Wednesday afternoon and evening. Rain showers may continue into Thursday. Friday...Sub-VFR possible with the chance for rain showers. && .MARINE... Southerly winds increase to around 10-15 kts, gusting up to 20 kts by this afternoon, but the conditions are expected to stay below Small Craft Advisory levels. Seas around 3-4 feet. Winds and seas lessening some overnight. Outlook... Tuesday through Wednesday...Southwest winds increase through the day Tuesday with Small Craft Advisory conditions possible by Tuesday afternoon as wind gusts reach near 25 kt. Seas look to start to reach near 5 feet as well Tuesday evening. Seas lessen by Wednesday morning but elevated winds out of the southwest remain through the day Wednesday with gusts near 25 kt. Showers and potentially some isolated thunderstorms move through Wednesday afternoon into early Wednesday night. Thursday...Conditions expected to be below Small Craft Advisory criteria by this time but showers may linger. Friday...Conditions are expected to be below Small Craft Advisory criteria. There is the chance for some rain showers. Rip Currents... Monday, south-southeast winds will be 10 to 15 mph with breaking waves of 1 to 2 feet. There will be a southeasterly swell with a period of around 8 seconds. As a result, there is a MODERATE risk for the development of dangerous and life threatening rip currents at the Jersey Shore and a LOW risk at Delaware Beaches where winds will be more shore parallel. Tuesday, south-southwesterly winds of 10-20 mph with breaking waves of 2 to 3 feet. A southeasterly swell will remain, though the period may be slightly shorter. For now, have opted for a MODERATE risk for the development of dangerous and life threatening rip currents for all NJ and DE beaches. Important to note that while surface temperatures inland will be in the upper 80s to low 90s on Monday, and low to mid 90s Tuesday, temperatures along the coasts will mainly be in the 70s to near 80 due to ocean temperatures in the 50s. These cold water temperatures can quickly cause hypothermia and physical incapacitation to anyone suddenly immersed in the water. For specific beach forecasts, visit weather.gov/beach/phi && .CLIMATE... Near record breaking temperatures are forecast from today through Wednesday. High temperatures Tuesday and low temperatures Wednesday morning could challenge monthly all time records for May. Records for our climate sites are listed below: Monthly Record High Temperatures for May Site Record/Date Allentown (ABE) 97/May 19, 1962 AC Airport (ACY) 99/May 29, 1969 AC Marina (55N) 95/May 31, 1895 & May 23, 1925 Georgetown (GED) 98/May 28, 1991 Mount Pocono (MPO) 94/May 22, 1911 Philadelphia (PHL) 97/May 30 & 31, 1991 Reading (RDG) 97/May 20, 1996 Trenton (TTN) 99/May 23, 1911 & May 31, 1986 Wilmington (ILG) 98/May 10, 1895 & May 30, 1895 Monthly Record Warmest Low Temperatures for May Site Record/Date Allentown (ABE) 71/May 31, 1975, May 28 & 31, 1991 AC Airport (ACY) 73/May 24, 2004 & May 19, 2017 AC Marina (55N) 73/May 30 & 31, 1987, & May 31, 1991 Georgetown (GED) 74/May 23, 1953 & May 20, 2019 Mount Pocono (MPO) 68/May 21, 1996 Philadelphia (PHL) 78/May 31, 1895 Reading (RDG) 72/May 28 & 31, 1939, & May 31, 1991 Trenton (TTN) 75/May 31, 1895 Wilmington (ILG) 75/May 30, 1895 Record High Temperatures May 18 Site Record/Year Allentown (ABE) 96/1962 AC Airport (ACY) 93/1987 AC Marina (55N) 90/1987 Georgetown (GED) 91/1974 Mount Pocono (MPO) 87/1962 Philadelphia (PHL) 94/1962 Reading (RDG) 96/1962 Trenton (TTN) 96/1986 Wilmington (ILG) 94/1962 Record Warmest Low Temperatures May 18 Site Record/Year Allentown (ABE) 65/2017 AC Airport (ACY) 70/2017 AC Marina (55N) 66/2017 Georgetown (GED) 72/2017 Mount Pocono (MPO) 61/2017 Philadelphia (PHL) 72/2017 Reading (RDG) 67/1900, 1943, & 2017 Trenton (TTN) 71/2017 Wilmington (ILG) 72/2017 Record High Temperatures May 19 Site Record/Year Allentown (ABE) 97/1962 AC Airport (ACY) 96/1962 AC Marina (55N) 92/1998 Georgetown (GED) 96/1962 Mount Pocono (MPO) 89/1962 Philadelphia (PHL) 96/1962 Reading (RDG) 96/1962 Trenton (TTN) 96/1962 Wilmington (ILG) 95/1962 Record Warmest Low Temperatures May 19 Site Record/Year Allentown (ABE) 65/2017 AC Airport (ACY) 73/2017 AC Marina (55N) 68/1998 Georgetown (GED) 73/2017 Mount Pocono (MPO) 60/1943 Philadelphia (PHL) 74/1877 Reading (RDG) 68/1962 Trenton (TTN) 70/2017 Wilmington (ILG) 70/2017 Record High Temperatures May 20 SiteRecord/Year Allentown (ABE) 92/1962 & 1996 AC Airport (ACY) 96/1996 AC Marina (55N) 93/1996 Georgetown (GED) 95/1962 Mount Pocono (MPO) 89/1996 Philadelphia (PHL) 94/1962 & 1996 Reading (RDG) 97/1996 Trenton (TTN) 94/1996 Wilmington (ILG) 96/1996 Record Warmest Low Temperatures May 20 Site Record/Year Allentown (ABE) 66/2019 AC Airport (ACY) 68/1996 AC Marina (55N) 69/1996 Georgetown (GED) 74/2019 Mount Pocono (MPO) 61/1959 Philadelphia (PHL) 71/2019 Reading (RDG) 69/1959 & 1996 Trenton (TTN) 68/1903, 1959, & 1962 Wilmington (ILG) 70/2019 && .PHI WATCHES/WARNINGS/ADVISORIES... PA...Heat Advisory from noon today to 8 PM EDT Tuesday for PAZ070- 071-104-106. NJ...Heat Advisory from noon today to 8 PM EDT Tuesday for NJZ015- 017>019. DE...None. MD...None. MARINE...None. && $$ DISCUSSION...AKL/Fitzsimmons/Staarmann AVIATION...AKL/Staarmann MARINE...AKL/Staarmann  335 FXUS61 KBGM 181021 AFDBGM Area Forecast Discussion National Weather Service Binghamton NY 621 AM EDT Mon May 18 2026 .WHAT HAS CHANGED... No significant changes have been made with this forecast update. && .KEY MESSAGES... 1) A strengthening ridge of high pressure will be our main feature today and tomorrow leading to above average temperatures and increasing humidity. A few isolated afternoon showers and thunderstorms are possible today and tomorrow afternoon. 2) A cold front will bring the potential for widespread showers and thunderstorms Wednesday afternoon, then cooler conditions return for the second half of the week. && .DISCUSSION... KEY MESSAGE 1... Surface high pressure anchored near Bermuda and a strengthening upper level ridge off the southeast coast will build northward today through tomorrow. This will allow southwesterly flow to settle over the region, promoting strong warm air advection and increasing dew points. As a result summer like conditions are expected for the start of the week with highs climbing into the mid 80s to low 90s. Forecast highs are near daily records, with record highs of 87 at KBGM both days, 93 Monday and 92 Tuesday at KAVP, and 90 Monday and 92 Tuesday at KSYR. Although yesterdays NBM guidance appeared too warm, observed high temperatures ended up closer to the NBM output than expected. However, with the NBM still running warmer than most guidance, the ongoing trend of slightly lowering maximum temperatures was continued for today and tomorrow, especially with NBM forecasting temperatures above daily records. As mentioned, dew points will be on the rise, reaching the low to mid 60s today and tomorrow, with some spots even reaching the upper 60s tomorrow afternoon, so the humidity will be noticeable. However there remains some uncertainty in whether scattered clouds and isolated showers or thunderstorms to pop up during the afternoon and early evening hours today and tomorrow as a couple of weak waves embedded in the flow around the ridge move through. Both the GFs and ECMWF continue to show an EML plume moving into the region this afternoon, with NAM guidance indicating CAPE values approaching 2000 J/Kg along with steep lapse rates. Despite the instability in place, model soundings continue to show a cap associated with the ridge axis overhead, which should largely suppress convective development. That said, if any storms are able to break the cap, the environment could support a few isolated severe storms. KEY MESSAGE 2... The next opportunity for widespread showers and thunderstorms will be with a cold front moving into the region on Wednesday. Model guidance continues to show the bulk of the convection moving through from midday through the afternoon. With the showers moving through earlier over the northwestern portion of our region, there will be a relatively large temperatures gradient with highs in the upper 60s to low 70s over the Finger Lakes region NY and highs in the low to mid 80s over the Pocono Mountain region PA. If everything can come together, some locally strong to severe thunderstorms can't be ruled out for the afternoon and early evening especially across NE PA and the southern Catskills. Cooler temperatures follow behind the front with highs returning to the mid 50s to mid 60s by the second half of the week. && .AVIATION /12Z MONDAY THROUGH FRIDAY/... Current fog at ELM should dissipate before or very soon after 12z. Otherwise, VFR conditions expected through the 12z TAF period. Outlook: Monday night...Mainly VFR; slight chance for afternoon isolated showers/thunderstorms with brief MVFR/IFR restriction possible. Tuesday...Mainly VFR, but afternoon scattered showers and thunderstorms may result in brief restrictions. Wednesday...Scattered showers and thunderstorms and associated restrictions possible as a frontal boundary moves into the area. Thursday and Friday...Mainly VFR. && .BGM WATCHES/WARNINGS/ADVISORIES... PA...None. NY...None. && $$ DISCUSSION...DK/ES AVIATION...KL  342 FXUS62 KRAH 181021 AFDRAH Area Forecast Discussion National Weather Service Raleigh NC 620 AM EDT Mon May 18 2026 .WHAT HAS CHANGED... * No significant changes. && .KEY MESSAGES... As of 120 AM Monday... 1) Hot and mainly dry through Wednesday. 2) Increasingly unsettled starting Wed night, with highest rain chances expected to be Thu. Low confidence in high temps Thu and Fri. && .DISCUSSION... As of 120 AM Monday... KEY MESSAGE 1... Hot and mainly dry through Wednesday. Still anticipate multiple days of anomalously hot temperatures. Mid- upper level troughing from Saskatchewan/Manitoba down through the N Plains and Rockies will ensure maintenance of strong ridging over and off the Southeast coast through midweek (although this is complicated by a weak but persistent upper low NW of the Bahamas). The LREF continues to show 500 mb heights over NC reaching the 95th- 99th percentile into Wed. Meanwhile, at the surface, Bermuda high pressure continues to extend westward across NC, keeping low level moisture return limited, with deep mixing each day and minimal cloudiness overall. Multi-model low level thicknesses continue to be around 20 m above normal today through Wed, supporting highs from around 90 to the mid 90s given high insolation. Early-day dewpoints in the 60s are likely to mix out and drop into the 50s during the hottest parts of each day, which should keep heat index values from rising into the triple digits. However, this kind of early-season heat can still be unexpectedly dangerous, as people have not yet become acclimated to the hot weather. The daily experimental Heat Risk is expected to peak at Moderate (level 2 of 4) today through Wed, indicating that this kind of heat is quite unusual for this time of year and has historically led to high levels of heat illness, with sensitive individuals and those without adequate cooling particularly vulnerable. And with just a modest breeze and lots of sunshine each day, the WBGT index will also be elevated, so spending time in the shade is encouraged, especially for those working or exercising outdoors. KEY MESSAGE 2... Increasingly unsettled starting Wed night, with highest rain chances expected to be Thu. Low confidence in high temps Thu and Fri. Confidence is high that the southern Canada portion of the mid-upper level trough will shift E over Ontario/Quebec and far E Canada Tue through Thu, allowing a cool surface high to spread across the N Great Lakes and St Lawrence Valley, reinforced by confluent flow aloft over the Northeast, which will help push a backdoor front southward into NC Thu. Precisely when this front arrives will drive both Thu high temps and precip chances. The deterministic GFS and ECMWF have trended toward a slightly slower arrival in their last few runs and are a bit slower than the latest LREF mean, indicating that at least our southern areas will likely stay in the warm sector longer, suggesting highs in the low 90s. Northern areas, especially near the VA border, have the largest temp spread among deterministic models and ensemble members, including the NBM's 15-20 degree 25th- 75th percentile spread for highs at Roxboro. Expect highs in the lower to upper 80s N of Hwy 64, but confidence in temps at any particular location is low. By Fri morning, the front is expected to settle across the S Piedmont and S Sandhills through the S/E Coastal Plain as the surface high center shifts ESE over the Northeast states, setting up a short-lived cold-air damming scenario, with stability reinforced by overrunning flow (albeit shallow) atop the wedging ridge. Highs NW of Hwy 1 are likely to be no warmer than the 70s, with some upper 60s for highs expected in the far N and NW Piedmont, while the far SE CWA should reach the low 80s. The greatest uncertainty with Fri high temps, however, will be through the heart of the CWA, including in the Triangle, as temps will depend on where the wedge boundary sets up. This high to our N and NE will be transitory, and as such we should see this wedge dissolve by Sat, leading to rebounding temps back to near to above normal values by the weekend as mid-upper ridging builds back over the Carolinas. Regarding pops, the highest rain chances look to be with and just behind the front, peaking Thu afternoon and night with an uptick in moist upglide, especially over the NW CWA within the deepest overrunning flow. Overall, the chance for showers and isolated to scattered storms will be above climatology Thu through the upcoming weekend, as our 925-850 mb flow strengthens from the SE and S, drawing in both Gulf and Atlantic moisture while weak perturbations ride within the SW flow from N Mexico and the TX Gulf Coast into the Carolinas. Coverage should be highest overall from the NW Piedmont to our W, where PW is expected to be highest within low level confluent flow and beneath weak DPVA and minor jet streaks to force ascent. Isolated pockets of heavy rain can't be ruled out, although generally speaking, these high pops are good news for our drought- ravaged region. && .AVIATION /10Z MONDAY THROUGH FRIDAY/... As of 620 AM Monday... TAF period: With high pressure offshore, the forecast should be quiet with VFR almost a certainty. The one exception will be FAY - yesterday there was an MVFR ceiling for about 90 minutes, and vertical soundings show this should be a possibility again this morning. In addition, statistical guidance is suggesting that some MVFR fog could develop late tonight into early Tuesday morning. Otherwise, conditions should be mostly clear with southwest wind. Outlook: MVFR restrictions will be possible briefly at FAY and RWI Tuesday and Wednesday mornings. Dry VFR conditions are forecast through Wednesday. The chance of rain will increase from northwest to southeast Wednesday night, with restrictions and showers expected Thursday and Friday. && .CLIMATE... Record High Temperatures: May 18: KGSO: 95/1911 KRDU: 95/1906 KFAY: 96/1911 May 19: KGSO: 96/1911 KRDU: 95/1962 KFAY: 96/2022 May 20: KGSO: 95/1917 KRDU: 96/2022 KFAY: 99/2022 Record High Minimum Temperatures: May 18: KGSO: 70/2015 KRDU: 72/1896 KFAY: 71/2018 May 19: KGSO: 68/2018 KRDU: 70/2022 May 20: KGSO: 68/2022 KRDU: 69/2019 KFAY: 71/2022 May 21: KGSO: 67/2022 KRDU: 71/1898 KFAY: 71/2025 && .RAH WATCHES/WARNINGS/ADVISORIES... None. && $$ DISCUSSION...Hartfield AVIATION...Green  323 FXUS63 KAPX 181020 AFDAPX Area Forecast Discussion National Weather Service Gaylord MI 620 AM EDT Mon May 18 2026 .KEY MESSAGES... -Rounds of showers and storms continue across the Great Lakes Region through Tuesday with severe weather possible. -High pressure returns cool and quiet weather Wednesday through Friday. -Cool overnight low temperatures lead to widespread frost concerns beyond the midweek. && .DISCUSSION... Issued at 336 AM EDT Mon May 18 2026 Pattern Synopsis: Deep longwave midlevel troughing currently positioned over the North American Rockies with strong flow over the Great Lakes Region will continue to eject multiple energy waves into the northwoods, resulting in rounds of active weather for the next 48-72 hours. Surface low pressure develops over the Minnesota/Wisconsin Border while a warm front extends northward into southern Ontario north of the CWA. A hot and humid air mass remains settled over the region this morning, combined with afternoon diurnal heating processes to fire off convective-driven showers into the evening hours. Another round of showers and storms will persist this Tuesday as the aforementioned low tracks northeast directly over Northern Lower with an attached cold front, providing enough lift for widespread storms with a marginal chance for severe weather (per SPC outlook). Conditions turn quiet the second half of the workweek as the previously mentioned trough axis progresses northeast. Backside cool and dry air moves into the Great Lakes Region supported by mild ridging pattern building over the midlevels. Subsidence aloft and surface high pressure will support quiet and overall non-impactful weather through the second half of the workweek. Surface temperatures will fall this Wednesday into the 50s for highs with a post-frontal cP air influence, followed by mild ridging slowly building temperatures back to near climatological normals by the end of the work week. The only impacts to monitor will be dry atmospheric conditions that could potentially lead to some fire weather concerns and rapidly falling overnight lows generating widespread frost. Forecast Details: Showers and storms today and Tuesday... Today: A few showers remain possible this morning from a decaying upstream line, but the majority of the CWA will be under the influence of partly/mostly cloudy skies and hot/humid weather. Cloud cover will attempt to clear out in order to build instability in the afternoon before a line develops and sweeps across the region west to east. Hi-rez guidance depicts most convection developing during the afternoon/early evening hours, mainly west of I-75. Model soundings depict a “skinny” CAPE profile with enough instability to support single-celled thunderstorms along the line potentially creating severe criteria hail stones, wind gusts, and even one or two supercells to develop with rotation. That being said, criteria for all types of severe weather remain on the lower/essential end of values needed for storm development. The most likely outcome will be the widespread support for heavy rain as cloud layer shear is very low along Northern Lower compared to downstate convection. Tuesday: The aforementioned cold front will begin to sweep across the CWA during the day with enough lift to provide another round of convection Tuesday afternoon. Latest trends hint at more stability compared to Monday's setup as low pressure crosses directly overhead. Again, PWAT’s near climatological max’s, saturated mid levels, and instability will favor convective-driven rainfall across the majority of the CWA. Higher shear values would require training storms for any type of flooding, but afternoon diurnal heating processes will build enough instability to continue thunderstorms with a marginal risk for severe weather. High pressure returns cool and quiet weather Wednesday through Friday...Strong cold frontal passage will pull dry, cool cP air into the northwoods. Subsequent departing low pressure and subsidence aloft will return high pressure and quiet weather Tuesday night through the end of the work week. Dry low-level profiles and dew points falling to near freezing will lead to concerning RH levels that could be a threat regarding fire weather. Nevertheless, post- frontal temperatures will drop into the 50s this Wednesday, followed by the aforementioned ridging pattern to slowly warm surface temps throughout the rest of the week until reaching the upper 60s/low 70s. Frost concerns Tuesday night through Thursday night...Strong cold air advection and efficient radiational cooling processes will likely lead to frost development Tuesday through Thursday night as lows drop into the 30s. The coldest night will likely be the coldest as high pressure is centered over the Midwest, leading to clear skies and lows near freezing. The typically coldest areas of the CWA will likely fall below freezing into the upper 20s while areas closer to the lakes remain in the mid-30s. && .AVIATION /12Z TAFS THROUGH 12Z TUESDAY/... Issued at 618 AM EDT Mon May 18 2026 Low cloud deck with LIFR CIGs will likely hang around for a few more hours across parts of far northern lower and eastern upper -- sticking around the longest across areas north of the bridge. Daytime heating will help mixing and improve flight conditions with time. Scattered showers and storms are expected to form early this afternoon and track across most of northern Michigan. Current confidence is that these storms will from close to/just east of northwest lower TAF sites (MBL, TVC, PLN) and track east this afternoon and early evening, potentially impacting APN. Thunderstorm chances will end this evening with rain-free weather expected tonight. Winds will increase out of the southwest this morning with sustained winds around 10-15 kts and gusts to 20-30 kts at times into this evening. IFR/LIFR CIGs look to return to parts of northern Michigan later tonight. && .APX WATCHES/WARNINGS/ADVISORIES... MI...None. MARINE...Small Craft Advisory until 8 PM EDT this evening for LMZ323- 341-342-344>346. Small Craft Advisory until noon EDT today for LSZ321-322. && $$ DISCUSSION...SJC AVIATION...DJC  384 FXUS61 KILN 181023 AFDILN Area Forecast Discussion National Weather Service Wilmington OH 623 AM EDT Mon May 18 2026 .WHAT HAS CHANGED... High temperatures Monday and Tuesday were adjusted down from the NBM. Wind gusts were increased this afternoon and Tuesday afternoon. && .KEY MESSAGES... 1) Warm conditions persist through Tuesday. The next cold front approaches the Ohio Valley on Tuesday, moving through the region late Tuesday night bringing renewed rain chances through midweek, followed by cooler temperatures behind the front for mid to late week. 2) Strong to severe storms will be possible Tuesday afternoon and Tuesday night. && .DISCUSSION... KEY MESSAGE 1) A period of well above normal temperatures will persist through Tuesday ahead of a cold front that passes through the area late Tuesday night. For today and Tuesday, high temperatures range from the mid-upper 80s to around 90. Temperatures on Wednesday are mitigated in the wake of the front, along with any showers and thunderstorms. Highs are expected to range from near 70 northwest to around 80 southeast. Temperatures cool behind the passage of the front Wednesday, lingering into Thursday. Temperatures climb back to above normal Friday and into the weekend. With the increase in temperatures and moisture, some unsettled weather will return for the weekend. Around the periphery of the mid and upper level ridge a corridor of moderate instability will allow thunderstorms to move into portions of west central Ohio and eastern Indiana late in the afternoon or early evening hours. The instability diminishes which will allow the storms to weaken quickly. Chance PoPs are limited to eastern Indiana and western Ohio, generally west of I-75. KEY MESSAGE 2) Moderate instability develops Tuesday with SBCAPE values around 2500 K/KG developing in the warm sector during the afternoon - ahead of an approaching sfc cold front. Forecast soundings indicate unidirectional wind flow with effective shear of 20 to 25 kts. Expect damaging winds with blowing segments to the the main threat. Hail will also be possible within the strongest storms, with this threat focused over the northwest. The severe threat decreases with eastward due to the likelihood for storms to arrive later in the evening or into the overnight as instability is decreasing. PWATs increase to 1.6 to 1.8 inches which will offer heavy rain rates and the potential for localized flooding. There continues to be some uncertainty regarding exact timing but at this time the most favored timeframe looks to be from 3 pm Tuesday afternoon to 3 AM Wednesday. && .AVIATION /12Z MONDAY THROUGH FRIDAY/... VFR conditions will prevail sans KLUK where morning valley fog has developed with MVFR to IFR visibility restrictions. The fog burns off quickly this morning. Few to scattered cumulus clouds will develop with heating this afternoon. Storms that develop west of the TAF sites decrease in coverage and intensity as they move east - so just have some mid and high level clouds later in the day into this evening. The best chance for observing a storm is at KDAY but even there the threat is too low to mention in the forecast. Southerly winds at 5 to 10 kt this morning increase during the day with gusts up to 25 kts this afternoon. OUTLOOK...Thunderstorms possible Tuesday afternoon into Tuesday night. MVFR ceilings and visibilities are possible Tuesday night into Wednesday and then again on Friday. && .ILN WATCHES/WARNINGS/ADVISORIES... OH...None. KY...None. IN...None. && $$ DISCUSSION...AR AVIATION...AR  379 FXUS65 KPIH 181023 AFDPIH Area Forecast Discussion National Weather Service Pocatello ID 423 AM MDT Mon May 18 2026 .KEY MESSAGES... - Gusty northerly winds diminishing later on today - Best chance of precipitation today across the southeast corner - Frost/freeze conditions through at least midweek before temperatures begin warming up && .DISCUSSION... Issued at 1209 AM MDT Monday May 18 2026 Strong low pressure will continue slowly churn to our south and east today. This will keep a persistent area of light rain and snow, with a few thunderstorms possible across the southeast corner. We could see snow falling at lowest elevations but anything that falls and accumulates should melt later in the day. Across the the higher elevations, a couple of inches are possible. We should also see a few showers across the central mountains south across the Magic Valley and Albion Mountains during the afternoon and evening hours. The bigger overall issue is strong northerly winds, which should be peaking early this morning, but lingering through the day. We do expect some spots to exceed the low end for WIND ADVISORY, but those pocket should be small enough to keep us from issuing something. That said, we are going to easily exceed the northeast wind threshold for American Falls Reservoir, therefore we will keep the LAKE WIND ADVISORY in place for today. The other issue is colder temperatures. We do have a FREEZE WARNING and FROST ADVISORY out for the Snake Plain and Magic Valley this morning. At the moment, the wind is helping keep temperatures pretty warm. However, we are seeing colder air slipping across the Montana border. That, in conjunction with the usual drop in temperatures overnight, we see no need to end the headlines in place for this morning. For tonight, with less wind, we are likely in line for another round of Frost/Freeze headlines. We will also have less cloud cover around. Highs today barely top out above 60 in a few spots. We should see a few showers and potentially isolated storms closer to the Montana border Tuesday afternoon and evening. At the moment, this may be a simple round of virga/sprinkles, but certainly worth mentioning in the forecast. Another wave drops south and east for a better chance of precipitation and thunderstorms Wednesday night and Thursday. We may see a few showers and storms daily heading into the weekend especially closer to the Montana border. Temperatures do eventually starting warming up, heading actually toward AVERAGE through midweek and ABOVE AVERAGE later in the week, as we switch from north/northwest flow to southwest flow. && .AVIATION /12Z TAFS THROUGH 12Z TUESDAY/... Issued at 419 AM MDT Mon May 18 2026 Breezy northerly winds will continue across eastern Idaho, slowly decreasing through the day. Gusts up to 30kts are possible across the area, with the strongest gusts at PIH, IDA, and DIJ. We have VCSH in place for this morning at DIJ, as showers linger for a bit longer. We will need to watch for a few possible late this afternoon and evening at SUN and BYI. At this point, it will take a pretty strong shower to drop conditions below VFR. Overnight, winds will be light. && .PIH WATCHES/WARNINGS/ADVISORIES... Freeze Warning until 9 AM MDT this morning for IDZ051-052. Frost Advisory until 9 AM MDT this morning for IDZ053>055. Lake Wind Advisory from 6 AM to 9 PM MDT Monday for IDZ054. && $$ DISCUSSION...Keyes AVIATION...Keyes  413 FXUS62 KILM 181024 AFDILM Area Forecast Discussion National Weather Service Wilmington NC 624 AM EDT Mon May 18 2026 .WHAT HAS CHANGED... Coastal Flood Advisories issued for Inland New Hanover, Coastal Horry and Coastal Georgetown counties. Updated 12Z TAF discussion. && .KEY MESSAGES... 1) Inland portions of the eastern Carolinas should see their longest heat wave of the year so far with 90 degree heat expected to continue through Thursday. 2) Rain chances should increase, especially inland, beginning Thursday as a front stalls near the Carolinas. && .DISCUSSION... KEY MESSAGE 1...Inland portions of the eastern Carolinas should see their longest heat wave of the year so far with 90 degree heat expected to continue through Thursday. A 590 dam upper ridge centered near the North Carolina coast is responsible for the sustained period of hot inland temperatures which should last through Thursday. Sinking air below the upper ridge should create a deep warm, dry layer extending down through 700 and 850 mb. Models have maintained their 850 mb temp forecasts of +17C to 18C (at or above the 90th percentile climatological values for this time of year) which increases confidence in our forecast of 90+ degree heat continuing through Thursday for locations more than 25 miles inland. Our forecast is for an additional four days (Monday through Thursday) of 90+ degree heat inland. Assuming that Florence and Lumberton highs touch 90 degrees this afternoon, this five day streak would eclipse this year's earlier streak of four days of 90 degree temps recorded from April 15-18 in both Florence and Lumberton. Coastal portions of the Carolinas should remain significantly cooler than inland due to sustained south winds dragging air across nearshore water still near 70 degrees. The upper ridge will become more narrow with time as an upper low strengthens across the northern Bahamas Tuesday into Wednesday. This feature looks a lot like an early season TUTT low, but any enhanced convection or other sensible weather impacts should remain far to our south. The arrival of a surface cold front Thursday afternoon should end this heat wave with temperatures returning toward normal for the coming weekend. KEY MESSAGE 2...Rain chances should increase, especially inland, beginning Thursday as a front stalls near the Carolinas. Dry weather will come to an end as early as Thursday morning. There's reasonable uncertainty on placement of highest POPs day to day as we deal with a stalled front in or near the area and the daily sea breeze. The front may lift north of the area into the weekend but the warm, humid air mass will continue to support rain chances through the end of the period. Little change in the difference between the NBM and other guidance with forecast POPs reflecting widespread showers/storms that I think will be more scattered near the boundaries. Calling rainfall totals this far out is tough but it does look like there's a signal for higher totals, mainly for the coastal areas, Friday into Saturday with the possibility of a passing low shoving more moisture onshore. Low confidence on the placement of this feature at this time. && .AVIATION /09Z MONDAY THROUGH FRIDAY/... Transient creek/swamp fog/stratus has made an appearance at CRE/ILM and will linger through 12Z or so before mixing out. VFR at all sites today. Sea breeze will again develop and push inland around midday with gusts 15-20 kt at the coast arriving at inland terminals mid to late afternoon. MVFR/IFR fog potential tonight with best chances once again along the coast. Inland sites will have slightly higher chances Tue morning compared to this morning due to increased boundary layer moisture. Extended Forecast...VFR through Wednesday though morning fog potential increases each day. An approaching front could bring restrictions in scattered showers and storms Thursday and Friday. && .MARINE... Through Tonight...South to southeast flow across the waters continues today and tonight with Bermuda High in place. Sea breeze development by midday will enhance winds near shore with potential for gusts 15-20 kt within a few miles of land. Otherwise winds will be around 10 kt with minimal gusts. Combination of a weak southeast swell and weak southerly wind wave will keep seas 2-3 ft. Tuesday through Saturday...Bermuda high pressure remains in control through Thursday with onshore flow enhanced in the afternoons by the daily sea breeze. A could front will approach Thursday night into Friday but doesn't look to clear the coastal waters with SE winds prevailing. Showers and storms are possible Thursday onwards. && .ILM WATCHES/WARNINGS/ADVISORIES... NC...Coastal Flood Advisory from 10 PM this evening to 2 AM EDT Tuesday for NCZ107. SC...Coastal Flood Advisory from 8 PM to 11 PM EDT this evening for SCZ054-056. MARINE...None. && $$ WHAT HAS CHANGED...ILM KEY MESSAGES...TRA/LEW DISCUSSION...TRA/LEW AVIATION...III MARINE...III/LEW  475 FXUS62 KTAE 181026 AFDTAE Area Forecast Discussion National Weather Service Tallahassee FL 626 AM EDT Mon May 18 2026 ...New AVIATION... .KEY MESSAGES... Issued at 626 AM EDT Mon May 18 2026 - Hot temperatures are expected through mid week. There is a high chance of highs at or above 90 across the area with the Florida Big Bend having a low chance of highs at or above 95. The heat may affect those who are sensitive, especially without cooling/hydration. - Isolated afternoon and early evening showers and thunderstorms will return mid to late week. Gusty winds and locally heavy rainfall are the main concerns with any stronger storms that develop. && .SHORT TERM AND LONG TERM... (Today through next Sunday) Issued at 226 AM EDT Mon May 18 2026 Upper ridge will remain draped through the southeast US through Tuesday while an upper trough digs southward to off the western Baja coast. The slug of moisture aiding convection development today along I75 will drift west towards the eastern Panhandle and southeast Alabama Monday while drier air (PWATS <1 inch) moves in from the Atlantic. Therefore, rain chances will be favored in our western zones Monday while the remainder of the tri-state area will be mostly dry. Much like today, thunderstorms that develop will be capable of gusty to strong winds, locally heavy rainfall, and frequent lightning. Tuesday will continue the dry trend with minimal chances for rainfall. Upper ridge weakens beginning Wednesday as an upper low develops and translates west into the Bahamas. Moisture starts a gradual return Wednesday as well as rain chances on the GCSB. Meanwhile, a cold front will sit between the upper trough out west and the weakening ridge out east which will gradually stall to our north through northern Alabama and Georgia later this week. In response, winds turn more southerly which will be more favorable for development on the GCSB in the afternoon then interactions with the westward moving ECSB late afternoons and evenings. The front gradually weakens this weekend as the upper ridge strengthens once again and the Bahamas upper low gets shunted south. Rain chances gradually increase from 20-40% Thursday to 30-60% by next Sunday. Temperatures are fairly persistent with highs in the upper 80s to lower 90s and lows in the upper 60s to lower 70s. With the drier air and lower rain chances Tuesday through Thursday, this will be the hottest timeframe through next weekend. There is even a low chance for meeting or exceeding 95F in the Florida Big Bend and heat indices approaching 100F as well in isolated locations. && .AVIATION... (12Z TAFS) Issued at 626 AM EDT Mon May 18 2026 Light and variable winds this morning. Patchy fog may develop over the ECP and DHN terminals and lift shortly soon after. Winds will be southeasterly, and shift southerly this afternoon for our western terminals. VFR conditions are expected to prevail through the TAF period. There's a slight chance for showers and thunderstorms affecting the ECP and DHN terminals this afternoon and may affect cigs and vsbys. && .MARINE... Issued at 226 AM EDT Mon May 18 2026 Light to moderate east to southeast winds will continue through midweek as high pressure ridging remains draped across the Gulf waters. Easterly surges in the overnight hours will cause a slight uptick in winds, perhaps briefly reaching cautionary levels. Ridging weakens later this week as a cold front reaches the Mid South causing winds to become southerly. Chances increase for shower and thunderstorm activity across the Gulf waters next weekend. && .FIRE WEATHER... Issued at 226 AM EDT Mon May 18 2026 High dispersions are expected today across the Suwannee Valley and I- 75 corridor as mixing heights climb to near 7,000 feet with easterly transport winds around 10 mph. Elsewhere, winds will be more southerly to southeasterly, but mixing heights will be lower, yielding good dispersions. Scattered showers and thunderstorms are possible this afternoon in the eastern Florida panhandle and southeast Alabama as the seabreeze develops and pushes inland. A relatively dry period is on tap Tuesday through Thursday before better moisture arrives and rain chances gradually increase into the weekend. Good afternoon dispersions each day towards the weekend. && .HYDROLOGY... Issued at 226 AM EDT Mon May 18 2026 Isolated to scattered storms will be possible each day through the next week. These could produce locally heavy downpours, which may lead to some nuisance flooding, mainly in urban or poor drainage areas. However, widespread flooding concerns are not expected. Extreme to exceptional drought continues across the area. While the rain is beneficial, significant improvement in drought conditions is not expected. For more information on local drought impacts, please visit www.weather.gov/tae/DroughtInformationStatement. && .SPOTTER INFORMATION STATEMENT... Spotter activation is not requested. However, spotters are always encouraged to safely report significant weather conditions when they occur by calling the office or tweeting us @NWSTallahassee. && .PRELIMINARY POINT TEMPS/POPS... Tallahassee 92 70 92 70 / 0 0 10 10 Panama City 87 70 87 70 / 10 0 10 0 Dothan 90 67 89 68 / 20 0 10 0 Albany 91 67 90 68 / 0 0 0 0 Valdosta 92 66 92 67 / 0 0 10 0 Cross City 94 69 94 69 / 0 0 40 10 Apalachicola 83 73 83 73 / 10 0 0 0 && .TAE WATCHES/WARNINGS/ADVISORIES... FL...High Rip Current Risk from 2 PM EDT /1 PM CDT/ this afternoon through this evening for FLZ112-114-115. GA...None. AL...None. GM...None. && $$ SHORT TERM...Scholl LONG TERM....Scholl AVIATION...Montgomery MARINE...Scholl FIRE WEATHER...Scholl HYDROLOGY...Young  654 FXUS61 KBTV 181031 AFDBTV Area Forecast Discussion National Weather Service Burlington VT 631 AM EDT Mon May 18 2026 .WHAT HAS CHANGED... As of 627 AM EDT Monday... A quick update to the forecast was made to better reflect the current showers and thunderstorms moving across the area this morning. && .KEY MESSAGES... As of 300 AM EDT Monday... 1. Unseasonably warm temperatures will continue for the first half of the week, with high temperatures climbing into the upper 70s and 80s. Meanwhile, lake and river water temperatures remain dangerously cold across the region, and breezes on Lake Champlain may result in rough lake conditions. 2. Above normal temperatures are expected for the first half of the week ahead. 3. Cooler and drier conditions are favored Thursday through Friday before a transition back to seasonable temperatures and a wetter pattern. && .DISCUSSION... As of 300 AM EDT Monday... KEY MESSAGE 1: Building high pressure across the region will allow for unseasonable warmth to continue for the first portion of the week. A warm front lifting across the region this morning may bring a few chances of showers this morning, but as the day progresses drier conditions are expected to prevail. High temperatures this afternoon are expected to climb into the upper 70s and 80s areawide. Despite the extremely warm air temperatures, water temperatures are still quite frigid, so any recreators should be sure to take the proper precautions, including wearing a life jacket. In addition to the warm temperatures, southerly winds will continue to be a bit breezy throughout the day, especially in the Champlain Valley and along the lake due to channeled flow. A Lake Wind Advisory is in effect, with additional details in the Marine section below Tuesday looks to be the hottest day of the week, with high temperatures climbing into the 80s and near 90 under southwesterly flow. These temperatures will be the warmest of the year so far, especially after a cool start to the month, so it is important to remember to stay safe in warmer temperatures by staying hydrated and take frequent breaks if working outside. Dewpoints will also be trending upwards going into Tuesday, making it feel quite humid especially for this time of year. The warmth and humidity will result in increasing instability, which will support the development of showers and possible thunderstorms for Tuesday, which could impact how warm temperatures climb during the day Tuesday. A cold front is expected to cross the region on Wednesday, which will impact how warm we can get that day. At the moment, highs in the upper 60s to mid 80s look likely, with central and southern Vermont getting the warmest before the cold front and associated precipitation arrive. In addition to warmth during the days, our lows likely won't fall below the upper 50s and 60s until the cold front arrives, providing only some relief from heat overnight. KEY MESSAGE 2: The warm and humidity environment ahead of an approaching cold front will allow for increased chances of thunderstorm develop Tuesday and Wednesday. Latest CAM guidance shows plenty of instability across the region, with surface CAPE values anywhere from 500 to 1500 J/kg, with temperatures in the 80s to near 90 and dewpoints in the 60s. Forcing will be mainly from an upper level weak wave and its potential interactions with topography, while surface forcing looks minimal Tuesday afternoon into the overnight period, and mid level lapse rates don't look overly impressive. The primary hazard with any strong to severe storms that do develop look to be damaging winds. SPC has placed much of the region a Slight Risk for severe weather, so be sure to monitor the forecast especially if you have any outdoor plans. The maincold front looks to drop across the region on Wednesday, bringing higher chances of precipitation with it. As we get closer to the event, the timing of the cold front or fronts should become more set. Should the front be delayed, the potential for stronger storms would increase during the day on Wednesday with more time to destabilize. KEY MESSAGE 3: Temperatures trend much cooler Thursday behind Wednesday's front with northwest flow resulting in cold air advection and a return to highs in the 50s to around 60 degrees. Winds slow overnight with skies clearing; this may be a period of concern for some frost outside the Champlain Valley with lows in the mid/upper 30s for many locations, and low 40s for the Champlain Valley. Conditions are favored to remain dry into Friday with temperatures rising back to seasonal averages in the mid/upper 60s to around 70 degrees. Models begin to split on precipitation timing heading into the weekend. Consensus maintains some chances of showers increasing Saturday with more widespread rain Sunday. However, a number of models are beginning to hold onto the ridge longer delaying precipitation onset until the late weekend. Either way, a pattern shift to deep return flow from the Gulf Coast northeastward into the Northeast is appearing probable. This flow pattern would result in multiple days of rain potential once it sets up. && .AVIATION /07Z MONDAY THROUGH FRIDAY/... Through 06Z Tuesday...VFR conditions will likely persist despite some shower chances 10- 16Z. Highest chances of brief MVFR CIGs will be at SLK and EFK as showers roll through with lower chances for PBG/BTV. A lljet will sweep through in the same time frame promoting some LLWS for MSS/SLK/PBG/EFK. Surface winds at PBG could gust 20-30kts at times with favorable off-lake, channeled flow while most other terminals see gusts around 20kts. Gusts drop by 00Z with clouds thickening late in the period as a diffluent flow pattern moves over the region with some increasing elevated instability. Showers will be possible starting just outside the TAF period. Outlook... Tuesday: VFR. Chance SHRA, Chance TSRA. Tuesday Night: Mainly VFR, with local MVFR possible. Chance SHRA, Slight chance TSRA. Wednesday: VFR. Chance SHRA, Slight chance TSRA. Wednesday Night: VFR. NO SIG WX. Thursday: VFR. NO SIG WX. Thursday Night: VFR. NO SIG WX. Friday: VFR. NO SIG WX. && .MARINE... As of 300 AM EDT Monday... A Lake Wind Advisory is in effect for the Broad Waters of Lake Champlain. Channel southerly flow will result in winds increasing to 15 to 25 knots this afternoon, with even higher gusts possible. && .BTV WATCHES/WARNINGS/ADVISORIES... VT...None. NY...None. && $$ WHAT HAS CHANGED...Kremer DISCUSSION...Boyd/Kremer AVIATION...Boyd MARINE...Kremer  751 FXUS63 KILX 181034 AFDILX Area Forecast Discussion National Weather Service Lincoln IL 534 AM CDT Mon May 18 2026 .KEY MESSAGES... - There is a Slight Risk (level 2 of 5) for severe weather areawide today. While all severe weather hazards will be possible, damaging wind gusts in excess of 60 mph will be the most likely. - Additional thunderstorms will develop along an advancing cold front on Tuesday, with a Slight Risk (level 2 of 5) for severe weather in areas east of Interstate 55. Once again, damaging wind gusts in excess of 60 mph will be the most likely hazard. && .DISCUSSION... Issued at 318 AM CDT Mon May 18 2026 ...Active Convective Complex This Morning... Radar analysis early this morning reveals a robust linear Mesoscale Convective System (MCS) stretching from north-central Wisconsin down through southeast Iowa, central Missouri, and into eastern Kansas. Strong, consolidating cold pools have allowed a leading outflow boundary to outrun the primary convective line. Convective-allowing models (CAMs) exhibit high confidence that this system will maintain its structural integrity as it pushes eastward into the central Illinois forecast area later this morning. Sustaining this morning activity is a potent 40-50 kt low-level jet (LLJ) parked directly over central Illinois. This feature, working in tandem with subtle mid-level shortwaves embedded within the southwest flow aloft, is providing ample synoptic lift and elevated instability (MUCAPE around 1500 J/kg). While weak deep- layer shear > 30 kts) should keep the morning activity largely disorganized and sub-severe, mid-level dry air and localized evaporative cooling could help overcome the waning morning inversion, supporting isolated severe hail or localized downburst winds. As an interesting aside, numerous runs of the HRRR overnight depicted an area of 40-50 kt surface winds within the trailing stratiform region, in an otherwise unassuming area. While it is uncertain if the model is resolving a wake-low or meso-high feature, the trend bears close observation. If these winds materialize, a short- fused wind advisory or high wind warning may become necessary for a brief window this afternoon. ...Severe Potential This Afternoon... By early afternoon, attention shifts to areas near and east of a Taylorville-to- Champaign line. A compact shortwave trough is progged to lift northeastward out of southeast Missouri around 18z, enhancing background kinematic shear and dynamic forcing across a highly buoyant boundary layer. In this zone, temperatures climbing toward the 80-degree mark and dewpoints hovering near 70 degrees will yield SBCAPE values exceeding 2000 J/kg. While the incoming shortwave will likely spark an increase in convective coverage ahead of the main morning line, individual storm intensity remains somewhat conditional. An important limiting factor is that mid-level lapse rates will likely deteriorate through the afternoon as the residual Elevated Mixed Layer (EML) exits to the east. However, as deep- layer shear ticks upward across southeast Illinois later today, localized enhancements within the main convective line remain a possibility. This could yield bowing segments capable of producing the full spectrum of severe weather hazards as the line advances into the southeastern counties. As an interesting aside, numerous runs of the HRRR overnight depicted an area of 40-50 kt surface winds within the trailing stratiform region, in an otherwise unassuming area. While it is uncertain if the model is resolving a wake-low or meso-high feature, the trend bears close observation. If these winds materialize, a short- fused wind advisory or high wind warning may become necessary for a brief window this afternoon. The severethreat will not completely diminish after dark. Additional shortwaves interacting with the persistent 40-50 kt LLJ core will likely sustain elevated convective development ahead of the approaching cold front well into Tuesday morning. ...Conditional Severe Threat on Tuesday... Significant forecasting uncertainty shrouds the Tuesday period, primarily driven by nebulous synoptic forcing and the likelihood of extensive morning convective debris. If widespread cloud cover and rain persist deep into the morning hours, afternoon destabilization will be severely limited, rendering the severe weather threat highly conditional. At this juncture, the highest probability for boundary layer recovery exists near and south of the Interstate 72 corridor, extending through southeast Illinois ahead of the advancing cold front. Should adequate destabilization manifest, favorable instability and deep-layer shear profiles would initially support discrete supercellular structures. However, because the regional shear vectors are oriented nearly parallel to the surface frontal boundary, any discrete activity is expected to transition rapidly into a linear MCS as the front sweeps through Tuesday evening. ...Hydrological Concerns and High QPF Variability... Confidence remains exceptionally high that multiple rounds of convective rainfall will impact the entire region through Tuesday evening. However, the complex, training nature of this pattern introduces severe spatial discrepancies in expected precipitation totals. 48-hour HREF Localized Probability Match Mean (LPMM) QPF projections valid through 00z Wednesday demonstrate a stark variance, showing localized pockets picking up a mere quarter-inch while training cores could easily exceed 4.5 inches. Current model guidance continues to pinpoint the highest risk for these excessive, flood-producing rainfall totals along and south of the I-72 corridor, where repeated convective elements are most likely to anchor. ...Midweek Clearing Followed by a Wet Weekend Outlook... Wednesday through Thursday: A welcome pattern shift occurs mid- week as a cooler, significantly more stable post-frontal regime takes hold. Continental high pressure building into the Midwest will clear skies and lower humidity levels, offering a brief reprieve from the active weather. Friday through Sunday: The dry spell will be short-lived. Global deterministic models are in notably better agreement, signaling a return to a wetter, unsettled pattern by late week. As the surface high pressure slants eastward, a potent mid-level shortwave will advance across the central U.S. A steady plume of Gulf moisture combined with a series of minor shortwave impulses lifting northeast from the Southern Plains will keep central Illinois susceptible to multiple rounds of scattered showers. While weak kinematic profiles should heavily restrict the overall severe weather risk, a gradual build-up of instability over the weekend will support widespread thunderstorm development. && .AVIATION /12Z TAFS THROUGH 12Z TUESDAY/... Issued at 519 AM CDT Mon May 18 2026 A line of thunderstorms approaching from the west is expected to reach KPIA by 13Z, KSPI and KBMI by 15Z, and KDEC/KCMI by 16Z this morning. A three-hour TEMPO group has been included to account for IFR visibilities during the storms, with scattered showers likely to linger for several hours afterward under generally VFR conditions. Brief periods of degraded conditions are possible within the most intense storm cells. South winds are forecast to increase to 15-20 kts this morning, with gusts reaching 25-30 kts. Low-level wind shear is anticipated late tonight at regional terminals as 50 kt southwest winds return aloft. An additional round of thunderstorms will move in from thewest overnight before sunrise; a PROB30 group has been added to address this potential. && .ILX WATCHES/WARNINGS/ADVISORIES... None. && $$ KEY MESSAGES...MJA DISCUSSION...MJA AVIATION...MJA  769 FXUS65 KVEF 181035 AFDVEF Area Forecast Discussion National Weather Service Las Vegas NV 335 AM PDT Mon May 18 2026 .KEY MESSAGES... * Today's weather includes cool temperatures and decreasing winds before a warming trend takes place through the rest of the week. && .DISCUSSION...through Sunday. The trough responsible for yesterday's winds is centered over the Nevada-Utah state line as of midnight PDT/MST and will continue to move east this morning. Wind speeds will decrease areawide in response. Wind Advisories and High Wind Warnings remain in effect until 5 AM PST/MST this morning for most locations. Northerly winds remain in the Colorado River Valley this morning with gusts between 30 and 40 mph, which will bring waves of 2 to 4 feet on area lakes. A High Wind Warning will continue until 11 AM PDT/MST, but these winds will weaken in the afternoon. Also of interest is notably cooler temperatures today, with highs 10 to 15 degrees below normal for mid-May. This means highs in the upper 70s to low 80s for the Mojave Desert Valleys including Las Vegas and highs in the 60s to low 70s in the southern Great Basin and Owens Valley. However, these unseasonably cool temperatures will be short lived as high pressure rebuilds over the West Coast throughout the week. Highs return to near normal values by Wednesday and climb to 5 to 10 degrees above normal by Friday, lasting through the weekend. && .AVIATION...For Harry Reid...For the 12z Forecast Package...Northerly winds with gusts of 20-30 knots will continue through the morning hours before gradually easing in the afternoon. Wind direction will shift more northeasterly in the afternoon hours with wind speeds becoming 8 to 12 knots. Winds will shift back to the northwest late Monday night before resuming northeasterly direction Tuesday by late morning. Otherwise, mostly clear skies are expected. For the rest of southern Nevada, northwest Arizona and southeast California...For the 12Z Forecast Package...Northerly wind directions are favored for most of the region on Monday with morning gusts in the 15 to 25 knot range. Exception will be along the Colorado River Valley near KIFP and KEED where gusts of 25 to 35 knots are possible. Wind gusts will gradually ease areawide by late in the day. Mostly clear skies are expected. && .SPOTTER INFORMATION STATEMENT...Spotters are encouraged to report any significant weather or impacts according to standard operating procedures. && $$ DISCUSSION...Meltzer AVIATION...Outler For more forecast information...see us on our webpage: https://weather.gov/lasvegas or follow us on Facebook and Twitter  766 FXUS66 KPDT 181035 AFDPDT Area Forecast Discussion National Weather Service Pendleton OR 335 AM PDT Mon May 18 2026 .KEY MESSAGES... - Breezy Gap winds Today and Tuesday - Pleasant weather for most of the week with a warming trend - Mountain showers in the Wallowas This afternoon && .DISCUSSION... GOES satellite showed cirrus overspreading east of the Cascades but mainly clear conditions across the much of eastern Oregon with the caveat of lingering mid level clouds from earlier rain showers over the Wallowas and northern Blue Mountains of Washington. Roughly 20 to 50 % chances remain for shower across the Wallowas This afternoon, where snow could mix in but is unlikely to accumulate even above 6500 ft AGL. Models going forward show a gradually building ridge across the PAC NW as 500 mb heights rise from about 564dm to 570 by Tuesday. This sunny high pressure setup will bring some modification to surface temperatures especially in the second half of the week where highs in the 80s should be returnable by Thursday and Friday. Westerly gap and valley winds will also be a diurnally driven sensible weather beginning with the Kittitas valley and the Eastern Columbia Gorge, and adjacent Blue Mountain foothills. Here, areas around Ellensburg has about 75% chances for wind gusts above 30 mph but little if any appreciable chances for gusts above 40 mph. Strongest winds in the region look to be along ridge tops. As the transition form the cooler airmass to the a warmer on on Wednesdays with the upper ridge becoming more centered across Washington and Oregon, the winds will become lighter over a broader area. && .AVIATION /12Z TAFS THROUGH 12Z TUESDAY/... Light and variable winds this morning will take time to develop more of a westerly trend, but by early afternoon, westerly gust to 20 and 30 mph can be common in DLS and YKM as gap winds develop across passes and valleys. Cirrus will be the primary clouds and VFR flight category is anticipated for all terminals. && .Preliminary Point Temps/PoPs... PDT 69 42 73 46 / 0 0 0 0 ALW 69 46 72 50 / 0 0 0 0 PSC 75 45 78 49 / 0 0 0 0 YKM 74 44 77 48 / 0 0 0 0 HRI 73 44 76 48 / 0 0 0 0 ELN 68 41 70 44 / 0 10 0 0 RDM 68 31 73 37 / 0 0 0 0 LGD 64 36 70 40 / 0 0 0 0 GCD 65 34 71 39 / 0 0 0 0 DLS 73 45 75 50 / 0 0 0 0 && .PDT WATCHES/WARNINGS/ADVISORIES... WA...None. OR...None. && $$ DISCUSSION...71 AVIATION...71  799 FXUS63 KILX 181036 CCA AFDILX Area Forecast Discussion National Weather Service Lincoln IL 534 AM CDT Mon May 18 2026 .KEY MESSAGES... - There is a Slight Risk (level 2 of 5) for severe weather areawide today. While all severe weather hazards will be possible, damaging wind gusts in excess of 60 mph will be the most likely. - Additional thunderstorms will develop along an advancing cold front on Tuesday, with a Slight Risk (level 2 of 5) for severe weather in areas east of Interstate 55. Once again, damaging wind gusts in excess of 60 mph will be the most likely hazard. && .DISCUSSION... Issued at 318 AM CDT Mon May 18 2026 ...Active Convective Complex This Morning... Radar analysis early this morning reveals a robust linear Mesoscale Convective System (MCS) stretching from north-central Wisconsin down through southeast Iowa, central Missouri, and into eastern Kansas. Strong, consolidating cold pools have allowed a leading outflow boundary to outrun the primary convective line. Convective-allowing models (CAMs) exhibit high confidence that this system will maintain its structural integrity as it pushes eastward into the central Illinois forecast area later this morning. Sustaining this morning activity is a potent 40-50 kt low-level jet (LLJ) parked directly over central Illinois. This feature, working in tandem with subtle mid-level shortwaves embedded within the southwest flow aloft, is providing ample synoptic lift and elevated instability (MUCAPE around 1500 J/kg). While weak deep- layer shear (> 30 kts) should keep the morning activity largely disorganized and sub-severe, mid-level dry air and localized evaporative cooling could help overcome the waning morning inversion, supporting isolated severe hail or localized downburst winds. As an interesting aside, numerous runs of the HRRR overnight depicted an area of 40-50 kt surface winds within the trailing stratiform region, in an otherwise unassuming area. While it is uncertain if the model is resolving a wake-low or meso-high feature, the trend bears close observation. If these winds materialize, a short- fused wind advisory or high wind warning may become necessary for a brief window this afternoon. ...Severe Potential This Afternoon... By early afternoon, attention shifts to areas near and east of a Taylorville-to- Champaign line. A compact shortwave trough is progged to lift northeastward out of southeast Missouri around 18z, enhancing background kinematic shear and dynamic forcing across a highly buoyant boundary layer. In this zone, temperatures climbing toward the 80-degree mark and dewpoints hovering near 70 degrees will yield SBCAPE values exceeding 2000 J/kg. While the incoming shortwave will likely spark an increase in convective coverage ahead of the main morning line, individual storm intensity remains somewhat conditional. An important limiting factor is that mid-level lapse rates will likely deteriorate through the afternoon as the residual Elevated Mixed Layer (EML) exits to the east. However, as deep- layer shear ticks upward across southeast Illinois later today, localized enhancements within the main convective line remain a possibility. This could yield bowing segments capable of producing the full spectrum of severe weather hazards as the line advances into the southeastern counties. As an interesting aside, numerous runs of the HRRR overnight depicted an area of 40-50 kt surface winds within the trailing stratiform region, in an otherwise unassuming area. While it is uncertain if the model is resolving a wake-low or meso-high feature, the trend bears close observation. If these winds materialize, a short- fused wind advisory or high wind warning may become necessary for a brief window this afternoon. Thesevere threat will not completely diminish after dark. Additional shortwaves interacting with the persistent 40-50 kt LLJ core will likely sustain elevated convective development ahead of the approaching cold front well into Tuesday morning. ...Conditional Severe Threat on Tuesday... Significant forecasting uncertainty shrouds the Tuesday period, primarily driven by nebulous synoptic forcing and the likelihood of extensive morning convective debris. If widespread cloud cover and rain persist deep into the morning hours, afternoon destabilization will be severely limited, rendering the severe weather threat highly conditional. At this juncture, the highest probability for boundary layer recovery exists near and south of the Interstate 72 corridor, extending through southeast Illinois ahead of the advancing cold front. Should adequate destabilization manifest, favorable instability and deep-layer shear profiles would initially support discrete supercellular structures. However, because the regional shear vectors are oriented nearly parallel to the surface frontal boundary, any discrete activity is expected to transition rapidly into a linear MCS as the front sweeps through Tuesday evening. ...Hydrological Concerns and High QPF Variability... Confidence remains exceptionally high that multiple rounds of convective rainfall will impact the entire region through Tuesday evening. However, the complex, training nature of this pattern introduces severe spatial discrepancies in expected precipitation totals. 48-hour HREF Localized Probability Match Mean (LPMM) QPF projections valid through 00z Wednesday demonstrate a stark variance, showing localized pockets picking up a mere quarter-inch while training cores could easily exceed 4.5 inches. Current model guidance continues to pinpoint the highest risk for these excessive, flood-producing rainfall totals along and south of the I-72 corridor, where repeated convective elements are most likely to anchor. ...Midweek Clearing Followed by a Wet Weekend Outlook... Wednesday through Thursday: A welcome pattern shift occurs mid- week as a cooler, significantly more stable post-frontal regime takes hold. Continental high pressure building into the Midwest will clear skies and lower humidity levels, offering a brief reprieve from the active weather. Friday through Sunday: The dry spell will be short-lived. Global deterministic models are in notably better agreement, signaling a return to a wetter, unsettled pattern by late week. As the surface high pressure slants eastward, a potent mid-level shortwave will advance across the central U.S. A steady plume of Gulf moisture combined with a series of minor shortwave impulses lifting northeast from the Southern Plains will keep central Illinois susceptible to multiple rounds of scattered showers. While weak kinematic profiles should heavily restrict the overall severe weather risk, a gradual build-up of instability over the weekend will support widespread thunderstorm development. && .AVIATION /12Z TAFS THROUGH 12Z TUESDAY/... Issued at 519 AM CDT Mon May 18 2026 A line of thunderstorms approaching from the west is expected to reach KPIA by 13Z, KSPI and KBMI by 15Z, and KDEC/KCMI by 16Z this morning. A three-hour TEMPO group has been included to account for IFR visibilities during the storms, with scattered showers likely to linger for several hours afterward under generally VFR conditions. Brief periods of degraded conditions are possible within the most intense storm cells. South winds are forecast to increase to 15-20 kts this morning, with gusts reaching 25-30 kts. Low-level wind shear is anticipated late tonight at regional terminals as 50 kt southwest winds return aloft. An additional round of thunderstorms will move in from the west overnight before sunrise; a PROB30 group has been added to address this potential. && .ILX WATCHES/WARNINGS/ADVISORIES... None. && $$ KEY MESSAGES...MJA DISCUSSION...MJA AVIATION...MJA  835 FXUS64 KLIX 181037 AFDLIX Area Forecast Discussion National Weather Service New Orleans LA 537 AM CDT Mon May 18 2026 ...New UPDATE, AVIATION... .KEY MESSAGES... Updated at 523 AM CDT Mon May 18 2026 - Isolated to scattered showers and storms will affect areas mainly west of the I-55 corridor today. A few storms may be locally strong and capable of locally heavy rainfall. - Showers and thunderstorms will spread further eastward toward the I-59 corridor Tuesday and Wednesday, with more area-wide coverage Thursday through next weekend. Some of these daily storms could become strong and/or produce locally heavy rainfall. - Temperatures are forecast to be generally near to warmer than normal through the next 7 days. && .UPDATE... Issued at 523 AM CDT Mon May 18 2026 Have trimmed back PoPs for today somewhat, as NBM numbers are coming a bit more in line with MAV/MET. While thunderstorm development can't be entirely precluded anywhere in the CWA today, the Baton Rouge area and points to the west have greater potential than anywhere else in our area. && .SHORT TERM... (Now through Thursday) Issued at 1213 AM CDT Mon May 18 2026 Upper ridging across much of the eastern half of the country tonight, with troughing over the Intermountain West. This is producing southwesterly upper flow just to our west. At the surface, a Bermuda High pattern extends west along the northern Gulf Coast. Frontal boundaries were over the Plains States. Temperatures and dew points were generally in the 70s during the late evening hours. With high pressure centered off the east coast, southeast winds will continue to bring moisture back into the area. A confluent zone between the high to our east and low pressure taking shape near the Four Corners is currently manifesting as a broad area of clouds stretching from southern Texas through the middle Mississippi Valley. The airmass remains rather moist with precipitable water values in the 1.6 to 1.8 range, in the neighborhood of the 90th percentile climatologically. Today and Tuesday will see similar conditions as we had on Sunday, although moisture may be a touch less, but not enough to make much difference in the soundings. The highest rain chances will generally across northwestern areas and an isolated threat of stronger storms producing gusty winds and heavy rainfall. To be honest, current forecast PoPs for both days look a bit on the high side, at least 10 percent or so today, but that isn't a big enough change to chase. Will see how today plays out, but the expectation is that rain chances tomorrow will probably need lowered across the western half of the forecast area later today. Shortwave energy Wednesday and Thursday will be much closer to the area and suppressing the ridge somewhat, so higher precipitation chances are entirely reasonable, but 80 percent at BTR seems a little high for this pattern, by probably 20 percent. Will hold for now, as neighbors grids haven't departed from NBM either. Little day to day change in temperature trends. One could probably get away with using persistence rather than guidance through much of the workweek. Cloud cover and timing of precipitation development would be the main factors in any departure from guidance, and those will change from day to day. && .LONG TERM... (Thursday night through Sunday) Issued at 1213 AM CDT Mon May 18 2026 The active southwesterly flow aloft will remain in place as the H5 ridge continues to reside over the northeast Gulf. Within the flow there will continue to be a series of upper level impulses that will help generate shower and thunderstorm activity, especially during the afternoon hours. The best potential for rainfall will be across the western half of the CWFA away from a bit stronger upperlevel subsidence in closer proximity to the ridge axis to our east. That said, there will be at least modest POPs for coastal MS. At this juncture, there will be a conditional severe threat...mostly associated with strong gusty winds. Additionally, the continued waves of showers and storms will also help produce at least a localized flooding threat, especially for the BTR area where there could be several days with afternoon convection. PWats are a also somewhat favorable with 1.5-1.8" with the higher values over the western portions of the CWFA. Again, this pattern pretty much locks in and remains in place throughout the long term period. With the increase in cloudiness and rain chances, temperatures will be a bit lower, but still around climo. (Frye) && .AVIATION... (12Z TAFS) Issued at 523 AM CDT Mon May 18 2026 Somewhat surprisingly, haven't really seen much in the way of low clouds this morning. Have seen a little development near KMCB in the last hour, but everyone else is VFR at this point. Do expect at least some MVFR ceilings to develop by mid-morning as cumulus field develops. Some potential for TSRA development this afternoon, but the only terminal the threat is high enough to mention is at KBTR, where PROB30 will be in place for late afternoon. Threat will be a little higher tomorrow afternoon. Also will have a threat of low ceilings/visibilities toward sunrise tomorrow, especially at KMCB (IFR or lower). && .MARINE... Issued at 1213 AM CDT Mon May 18 2026 Onshore flow will persist as high pressure remains anchored over the western Atlantic. A tightening pressure gradient between this high and low pressure across the plains states will lead to strengthening winds, especially west of the Mississippi River. Exercise Caution headlines will remain in effect through the overnight hours. As moisture increases across the region, he chance of daily showers and storms will gradually increase, with the best chances later in the week as a weak front approaches the area. Some storms will be capable of producing locally hazardous winds and waves. && .LIX WATCHES/WARNINGS/ADVISORIES... LA...None. GM...None. MS...None. GM...None. && $$ SHORT TERM...RW LONG TERM....RDF AVIATION...RW MARINE...RW  887 FXUS63 KILX 181038 CCA AFDILX Area Forecast Discussion National Weather Service Lincoln IL 534 AM CDT Mon May 18 2026 .KEY MESSAGES... - There is a Slight Risk (level 2 of 5) for severe weather areawide today. While all severe weather hazards will be possible, damaging wind gusts in excess of 60 mph will be the most likely. - Additional thunderstorms will develop along an advancing cold front on Tuesday, with a Slight Risk (level 2 of 5) for severe weather in areas east of Interstate 55. Once again, damaging wind gusts in excess of 60 mph will be the most likely hazard. && .DISCUSSION... Issued at 318 AM CDT Mon May 18 2026 ...Active Convective Complex This Morning... Radar analysis early this morning reveals a robust linear Mesoscale Convective System (MCS) stretching from north-central Wisconsin down through southeast Iowa, central Missouri, and into eastern Kansas. Strong, consolidating cold pools have allowed a leading outflow boundary to outrun the primary convective line. Convective-allowing models (CAMs) exhibit high confidence that this system will maintain its structural integrity as it pushes eastward into the central Illinois forecast area later this morning. Sustaining this morning activity is a potent 40-50 kt low-level jet (LLJ) parked directly over central Illinois. This feature, working in tandem with subtle mid-level shortwaves embedded within the southwest flow aloft, is providing ample synoptic lift and elevated instability (MUCAPE around 1500 J/kg). While weak deep- layer shear (> 30 kts) should keep the morning activity largely disorganized and sub-severe, mid-level dry air and localized evaporative cooling could help overcome the waning morning inversion, supporting isolated severe hail or localized downburst winds. As an interesting aside, numerous runs of the HRRR overnight depicted an area of 40-50 kt surface winds within the trailing stratiform region, in an otherwise unassuming area. While it is uncertain if the model is resolving a wake-low or meso-high feature, the trend bears close observation. If these winds materialize, a short- fused wind advisory or high wind warning may become necessary for a brief window this afternoon. ...Severe Potential This Afternoon... By early afternoon, attention shifts to areas near and east of a Taylorville-to- Champaign line. A compact shortwave trough is progged to lift northeastward out of southeast Missouri around 18z, enhancing background kinematic shear and dynamic forcing across a highly buoyant boundary layer. In this zone, temperatures climbing toward the 80-degree mark and dewpoints hovering near 70 degrees will yield SBCAPE values exceeding 2000 J/kg. While the incoming shortwave will likely spark an increase in convective coverage ahead of the main morning line, individual storm intensity remains somewhat conditional. An important limiting factor is that mid-level lapse rates will likely deteriorate through the afternoon as the residual Elevated Mixed Layer (EML) exits to the east. However, as deep- layer shear ticks upward across southeast Illinois later today, localized enhancements within the main convective line remain a possibility. This could yield bowing segments capable of producing the full spectrum of severe weather hazards as the line advances into the southeastern counties. The severe threat will not completely diminish after dark. Additional shortwaves interacting with the persistent 40-50 kt LLJ core will likely sustain elevated convective development ahead of the approaching cold front well into Tuesday morning. ...Conditional Severe Threat on Tuesday... Significant forecasting uncertainty shrouds the Tuesday period, primarily driven by nebulous synoptic forcing and the likelihood of extensive morning convective debris. If widespread cloud cover and rain persist deep into the morning hours, afternoon destabilization will be severely limited, rendering the severe weather threat highly conditional. At this juncture, the highest probability for boundary layer recovery exists near and south of the Interstate 72 corridor, extending through southeast Illinois ahead of the advancing cold front. Should adequate destabilization manifest, favorable instability and deep-layer shear profiles would initially support discrete supercellular structures. However, because the regional shear vectors are oriented nearly parallel to the surface frontal boundary, any discrete activity is expected to transition rapidly into a linear MCS as the front sweeps through Tuesday evening. ...Hydrological Concerns and High QPF Variability... Confidence remains exceptionally high that multiple rounds of convective rainfall will impact the entire region through Tuesday evening. However, the complex, training nature of this pattern introduces severe spatial discrepancies in expected precipitation totals. 48-hour HREF Localized Probability Match Mean (LPMM) QPF projections valid through 00z Wednesday demonstrate a stark variance, showing localized pockets picking up a mere quarter-inch while training cores could easily exceed 4.5 inches. Current model guidance continues to pinpoint the highest risk for these excessive, flood-producing rainfall totals along and south of the I-72 corridor, where repeated convective elements are most likely to anchor. ...Midweek Clearing Followed by a Wet Weekend Outlook... Wednesday through Thursday: A welcome pattern shift occurs mid- week as a cooler, significantly more stable post-frontal regime takes hold. Continental high pressure building into the Midwest will clear skies and lower humidity levels, offering a brief reprieve from the active weather. Friday through Sunday: The dry spell will be short-lived. Global deterministic models are in notably better agreement, signaling a return to a wetter, unsettled pattern by late week. As the surface high pressure slants eastward, a potent mid-level shortwave will advance across the central U.S. A steady plume of Gulf moisture combined with a series of minor shortwave impulses lifting northeast from the Southern Plains will keep central Illinois susceptible to multiple rounds of scattered showers. While weak kinematic profiles should heavily restrict the overall severe weather risk, a gradual build-up of instability over the weekend will support widespread thunderstorm development. && .AVIATION /12Z TAFS THROUGH 12Z TUESDAY/... Issued at 519 AM CDT Mon May 18 2026 A line of thunderstorms approaching from the west is expected to reach KPIA by 13Z, KSPI and KBMI by 15Z, and KDEC/KCMI by 16Z this morning. A three-hour TEMPO group has been included to account for IFR visibilities during the storms, with scattered showers likely to linger for several hours afterward under generally VFR conditions. Brief periods of degraded conditions are possible within the most intense storm cells. South winds are forecast to increase to 15-20 kts this morning, with gusts reaching 25-30 kts. Low-level wind shear is anticipated late tonight at regional terminals as 50 kt southwest winds return aloft. An additional round of thunderstorms will move in from the west overnight before sunrise; a PROB30 group has been added to address this potential. && .ILX WATCHES/WARNINGS/ADVISORIES... None. && $$ KEY MESSAGES...MJA DISCUSSION...MJA AVIATION...MJA  934 FXUS63 KPAH 181039 AFDPAH Area Forecast Discussion National Weather Service Paducah KY 539 AM CDT Mon May 18 2026 .KEY MESSAGES... - Breezy today with thunderstorms becoming a factor by the afternoon (50-70% chance). Some risk (level 1 to 2 of 5) for severe thunderstorms exists with wind and hail the main threat. - High rain chances (80-100%) from Tuesday afternoon into Tuesday night. Level 2 of 5 severe weather risk but the deep layer shear may be too weak. Locally heavy rain possible but storm organization may be too lacking for optimal rainfall rates. - Drier conditions briefly behind a cold front but rain and thunderstorms (and humidity) come back by Thursday into Friday. && .UPDATE... Issued at 539 AM CDT Mon May 18 2026 MCS over Missouri is slowly slinking southeastward into a more unstable airmass. Showers also starting to pop up over AR/MO. Adjusted timing of PoPs very slightly earlier to account for this with earliest pops by 9 to 10 am. MLCAPEs in SEMO are already about 2000 J/kg so a stronger storm or two would be possible with this initial activity in the 9-12 am range, mainly over SEMO. && .DISCUSSION... Issued at 118 AM CDT Mon May 18 2026 Things continue to move roughly in line with expectations in the near term, wetter in the medium/long-range. For today watching a shortwave over south central Texas that is progged to be overhead by 20-21z and looks to interact with our increasingly soupy airmass with dewpoints in the mid 60s to low 70s. Convection allowing models suggest the MCS over MO/KS may make it (in some form) into the region by about that time as well. The upper support looks a little lacking but may be sufficient to keep something going the trend is at least for it to generate some sort of differential heating boundary that may be a foci for convective initiation in the heat of the day. MLCAPEs are around 2000-2500 J/kg. Deep layer shear is 35-40 kt with the approaching wave, low shear is not too worrisome although a mesoscale boundary from the MCS could complicate the tornado factor a little. That risk appears highest along the I-64 corridor roughly, where it looks like most of the rest of the CWA could see isolated to scattered cells/complexes. These do appear they'd have the ingredients for wind/hail through the afternoon. Breezy conditions again today and did hoist another targeted Lake Wind Advisory. Tuesday a surface cold front still works close to the area as we begin to feel the lifting influence of the right rear exit region of a northern Plains/Great Lakes jet max. PWATs are high, layer warm-air advection is moderate, jet level ascent/height falls are supportive and you'll have the front in the area as well. We should end up with scattered to numerous showers and storms with a window for locally heavy rain - although there still really aren't any tools that go too nuts. HREF PMMs max out at 1.5 inches or so and it would take quite a bit more than that to flood given our antecedent conditions. Severe weather wise the instability will be there, the low shear is ok but the deep layer shear really backs off through the day and we may not quite have enough oomph there to help significantly organize convection. This may be part of why the CAM based precip guidance is so weak, things just will be too sloppy to produce optimal rainfall rates. The medium and long range trend is definitely for more persistent troughiness over the central plains and Rocky Mountains. Late Wednesday into Thursday may be a little drier/less humid but by Friday the warm front sweeps back to the north putting us firmly back into the soup. Shear/instabilityFriday may line up to produce a little severe weather potential with ECMWF/GFS agreement on shear and instability. After that fairly large differences in deterministic and ensemble positioning and shape of the cut off/closed lows/shortwave troughs that spit out of this system get pretty jumbled. On balance however generally humid and unsettled weather appears a reasonable bet. Hopefully with enough rain to ameliorate our drought conditions at least a little. && .AVIATION /00Z TAFS THROUGH 00Z MONDAY/... Issued at 515 PM CDT Sun May 17 2026 With high pressure affixed to the east and low pressure approaching from the west this package, the terminals remain within a tight gradient for sustained southerlies, including diurnal gustiness again tmrw. Some moistening of the profile takes place over the back half of the package, as the low and its associated front nears closer; this will lead to high end MVFR to low end VFR bases (SCT-BKN) developing, including low probs for -TSRA, esp going into the planning phase/heating hours of the afternoon. && .PAH WATCHES/WARNINGS/ADVISORIES... IL...Lake Wind Advisory from 11 AM this morning to 4 PM CDT this afternoon for ILZ075-081-085. MO...Lake Wind Advisory from 11 AM this morning to 4 PM CDT this afternoon for MOZ100. IN...None. KY...Lake Wind Advisory from 11 AM this morning to 4 PM CDT this afternoon for KYZ007>009-011-012. && $$ UPDATE...JGG DISCUSSION...JGG AVIATION...  026 FXUS61 KALY 181043 AFDALY Area Forecast Discussion National Weather Service Albany NY 643 AM EDT Mon May 18 2026 .WHAT HAS CHANGED... Marginal Risk (Level 1 of 5) for severe thunderstorms for Herkimer and Hamilton Counties today and tonight. Marginal (Level 1 of 5) to Slight Risk (Level 2 of 5) for severe thunderstorms Tue across most of eastern NY and western New England with damaging winds the main threat. Marginal Risk (Level 1 of 5) for isolated severe threat south and east of the Capital District on Wed. Winds/wind gusts slightly increased for Tue through Wed with frontal passage mid week, as cooler temps return late Wed-Thu. && .KEY MESSAGES... 1) Well above-normal temps continue into the mid-week. The NWS HeatRisk is in the moderate category for heat-related impacts, especially on Tue. 2) Coverage of showers and t-storms increases Tue pm into Wed ahead of a cold front. Some strong to potentially severe t-storms possible Tue pm/early evening and also Wed south of the Capital District. 3) A return to more seasonable temps is expected late this week with the next chance for widespread rain being next weekend. && .DISCUSSION... KEY MESSAGE 1... A mid and upper level ridge near the East Coast will bring above normal temps to the forecast area today-Tue. The ridge builds in this morning, as a weak frontal boundary lifts north, as a warm front with some isolated to widely scattered showers and t-storms over the southern Adirondacks and Lake George Region. Low and mid level heights increase 1-2+ STDEVs above normal based on the latest NAEFS. H850 temps will rise 2-3 STDEVS above normal by Tue with the actual temps in the +15C to +19C range. Max temps today will be in the upper 80s to lower 90s in the valleys and upper 70s to mid 80s over the higher terrain. Heat indices/apparent temps will be in the 80s to lower 90s. An isolated pop-up shower/t-storm can not be ruled out, especially late in the pm/early evening over the west/southwest Adirondacks. Isolated strong to damaging wind gusts are possible based on the SPC Day 1 Marginal Risk. Lows will be quite mild tonight in the 60s with some upper 50s over the higher terrain. The warmest day will be on Tue with max temps about 20 degrees above normal. The NBM continues to run warm and our forecast highs for Tue involves blending with persistence/prev fx and trimming by a few degrees based on H850 temps +16C to +19C with dewpts in the upper 50s to lower 60s (spotty mid 60s) was considered with the south/southwest boundary layer flow. Max temps will be more widespread in the lower 90s in the valleys and 80s over the hills and mtns. Some records could be tied or broken on Tue (see the Climate section below). A few isolated spots in the mid Hudson Valley may hit apparent temps/heat indices (feels-like temps) in the mid-90s, but the air temps will be close to the apparent temps. No heat advisories are planned at this time. However, the hot conditions with some moderate humidity levels have cause the NWS HeatRisk to be in the moderate category for most of the forecast area on Tue (spotty in the major category in the mid Hudson Valley). This category affects the population that are sensitive to heat, especially those without cooling systems/hydration, and some health systems and industries. The heat subsides by Wed with a cold frontal passage with some showers and t-storms. KEY MESSAGE 2... The coverage and intensity of convection is still uncertain Tue-Wed across eastern NY and western New England. SPC continues a Marginal (Level 1 of 5) to Slight Risk (Level 2 of 5) for severe weather across the forecast area Tue-Tue night. Some of the CAMs indicate a pre-frontal sfc trough/lake breeze boundary may focus convection in the afternoon (mid to late pm) and it extends into the early evening. The 0-6 km shear does not look exceptionally strong at 25-35 KT, but MLCAPEs may reach 1000-1500 J/kg especially along or north and west of Albany. The Slight Risk covers the western Mohawk Valley, southern Adirondacks and the Lake George Region. Steep low-level lapse rates will be in place with DCAPEs around 1000 J/kg. The latest ARW-WRF 1 & 2 support more coverage than the 3-km NAM or HRRR. The atmosphere becomes less capped with the front approaching Tue night. It becomes breezier ahead of the front. The main threat with any severe thunderstorms will be damaging winds. The instability wanes Tue night with the frontal boundary placement tricky for Wed. The latest forecast supports the front near the Capital District, southern VT and the northern Catskills in the late morning early pm and moving south quickly. The latest NBM probabilities for >1000 J/kg of SBCAPE Wed early pm are surpressed south and east of the Tri Cities towards the mid Hudson Valley and I-84 corridor. A few t-storms could be on the strong side closer to this area. SPC Day 3 Outlook has a Marginal Risk (Level 1 of 5) for locations south and east of the Capital District Wed pm for damaging wind gusts. It will become breezy in the wake of the front with west to northwest winds 10-20 mph with some gusts 25-35 mph. Max temps may range from the 60s to lower 70s over the western Mohawk/southern Dacks to the upper 80s to lower 90s over the mid Hudson Valley and NW CT. The Capital Region was favored in the upper 70s to lower 80s. Much cooler air filters in Wed night. KEY MESSAGE 3... Strong cold advection continues across the region Wed night with lows in the 40s to lower 50s with some upper 30s in the Adirondack Park, as the growing season begins there May 21st. A 1030 hPa sfc anticyclone builds in from southern Ontario and the Great Lakes Region on Thu. Temps will be near or slightly below normal in the 50s to lower 60s over the higher terrain and mid and upper 60s in the valleys. The cooler and drier weather continues Thu night thru Fri with some patchy to areas of frost possible in the southern Adirondacks. Wetter and more unsettled weather returns potentially Fri night into the Memorial Day Holiday weekend, as a warm front and a low pressure system may bring occasional showers with slightly cooler than normal temps. && .AVIATION /12Z MONDAY THROUGH FRIDAY/... Through 12Z Tuesday, mainly VFR conditions are expected through the TAF period. However, upper level disturbances could bring a few showers to KGFL until 14Z/Mon, and again 00Z-03Z/Tue. Brief MVFR/IFR Vsbys could occur within any heavier downpours. Light/variable winds will become southeast to south and increase to 8-12 KT by late morning, with some gusts of 15-20 KT possible this afternoon. South winds will persist after sunset at 5-10 KT. Low level wind shear is expected overnight as sfc winds decrease to less than 10 KT, while winds around 2000 FT AGL increase from the southwest to west at 30-35 KT. Outlook... Tuesday Night: No Operational Impact. NO SIG WX. Wednesday: High Operational Impact. Breezy. Likely SHRA...TSRA. Wednesday Night: Low Operational Impact. Breezy. NO SIG WX. Thursday: Low Operational Impact. Breezy. NO SIG WX. Thursday Night: No Operational Impact. NO SIG WX. Friday: Low Operational Impact. NO SIG WX. && .CLIMATE... High Temperature Records: May 19 - Tuesday Albany, NY: 91 degrees set in 1989 Glens Falls, NY: 88 degrees set in 1989 Poughkeepsie, NY: 96 degrees set in 1962 && .ALY WATCHES/WARNINGS/ADVISORIES... CT...None. NY...None. MA...None. VT...None. && $$ DISCUSSION...15 AVIATION...24 CLIMATE...31  025 FXUS63 KILX 181043 CCC AFDILX Area Forecast Discussion National Weather Service Lincoln IL 534 AM CDT Mon May 18 2026 .KEY MESSAGES... - There is a Slight Risk (level 2 of 5) for severe weather areawide today. While all severe weather hazards will be possible, damaging wind gusts in excess of 60 mph will be the most likely. - Additional thunderstorms will develop along an advancing cold front on Tuesday, with a Slight Risk (level 2 of 5) for severe weather in areas east of Interstate 55. Once again, damaging wind gusts in excess of 60 mph will be the most likely hazard. && .DISCUSSION... Issued at 318 AM CDT Mon May 18 2026 ...Active Convective Complex This Morning... Radar analysis early this morning reveals a robust linear Mesoscale Convective System (MCS) stretching from north-central Wisconsin down through southeast Iowa, central Missouri, and into eastern Kansas. Strong, consolidating cold pools have allowed a leading outflow boundary to outrun the primary convective line. Convective-allowing models (CAMs) exhibit high confidence that this system will maintain its structural integrity as it pushes eastward into the central Illinois forecast area later this morning. Sustaining this morning activity is a potent 40-50 kt low-level jet (LLJ) parked directly over central Illinois. This feature, working in tandem with subtle mid-level shortwaves embedded within the southwest flow aloft, is providing ample synoptic lift and elevated instability (MUCAPE around 1500 J/kg). While weak deep- layer shear (> 30 kts) should keep the morning activity largely disorganized and sub-severe, mid-level dry air and localized evaporative cooling could help overcome the waning morning inversion, supporting isolated severe hail or localized downburst winds. As an interesting aside, numerous runs of the HRRR overnight depicted an area of 40-50 kt surface winds within the trailing stratiform region, in an otherwise unassuming area. While it is uncertain if the model is resolving a wake-low or meso-high feature, the trend bears close observation. If these winds materialize, a short- fused wind advisory or high wind warning may become necessary for a brief window this afternoon. ...Severe Potential This Afternoon... By early afternoon, attention shifts to areas near and east of a Taylorville-to- Champaign line. A compact shortwave trough is progged to lift northeastward out of southeast Missouri around 18z, enhancing background kinematic shear and dynamic forcing across a highly buoyant boundary layer. In this zone, temperatures climbing toward the 80-degree mark and dewpoints hovering near 70 degrees will yield SBCAPE values exceeding 2000 J/kg. While the incoming shortwave will likely spark an increase in convective coverage ahead of the main morning line, individual storm intensity remains somewhat conditional. An important limiting factor is that mid-level lapse rates will likely deteriorate through the afternoon as the residual Elevated Mixed Layer (EML) exits to the east. However, as deep- layer shear ticks upward across southeast Illinois later today, localized enhancements within the main convective line remain a possibility. This could yield bowing segments capable of producing the full spectrum of severe weather hazards as the line advances into the southeastern counties. The severe threat will not completely diminish after dark. Additional shortwaves interacting with the persistent 40-50 kt LLJ core will likely sustain elevated convective development ahead of the approaching cold front well into Tuesday morning. ...Conditional Severe Threat on Tuesday... Significant forecasting uncertainty shrouds the Tuesday period, primarily driven by nebulous synoptic forcing and the likelihood of extensive morning convective debris. If widespread cloud cover and rain persist deep into the morning hours, afternoon destabilization will be severely limited, rendering the severe weather threat highly conditional. At this juncture, the highest probability for boundary layer recovery exists near and south of the Interstate 72 corridor, extending through southeast Illinois ahead of the advancing cold front. Should adequate destabilization manifest, favorable instability and deep-layer shear profiles would initially support discrete supercellular structures. However, because the regional shear vectors are oriented nearly parallel to the surface frontal boundary, any discrete activity is expected to transition rapidly into a linear MCS as the front sweeps through Tuesday evening. ...Hydrological Concerns and High QPF Variability... Confidence remains exceptionally high that multiple rounds of convective rainfall will impact the entire region through Tuesday evening. However, the complex, repeated nature of this pattern introduces severe spatial discrepancies in expected precipitation totals. 48-hour HREF Localized Probability Match Mean (LPMM) QPF projections valid through 00z Wednesday demonstrate a stark variance, showing localized pockets picking up a mere quarter-inch while repeating strom cores could exceed 4.5 inches. Current model guidance continues to pinpoint the highest risk for these excessive, flood-producing rainfall totals along and south of the I-72 corridor, where repeated convective elements are most likely to anchor. ...Midweek Clearing Followed by a Wet Weekend Outlook... Wednesday through Thursday: A welcome pattern shift occurs mid- week as a cooler, significantly more stable post-frontal regime takes hold. Continental high pressure building into the Midwest will clear skies and lower humidity levels, offering a brief reprieve from the active weather. Friday through Sunday: The dry spell will be short-lived. Global deterministic models are in notably better agreement, signaling a return to a wetter, unsettled pattern by late week. As the surface high pressure slants eastward, a potent mid-level shortwave will advance across the central U.S. A steady plume of Gulf moisture combined with a series of minor shortwave impulses lifting northeast from the Southern Plains will keep central Illinois susceptible to multiple rounds of scattered showers. While weak kinematic profiles should heavily restrict the overall severe weather risk, a gradual build-up of instability over the weekend will support widespread thunderstorm development. && .AVIATION /12Z TAFS THROUGH 12Z TUESDAY/... Issued at 519 AM CDT Mon May 18 2026 A line of thunderstorms approaching from the west is expected to reach KPIA by 13Z, KSPI and KBMI by 15Z, and KDEC/KCMI by 16Z this morning. A three-hour TEMPO group has been included to account for IFR visibilities during the storms, with scattered showers likely to linger for several hours afterward under generally VFR conditions. Brief periods of degraded conditions are possible within the most intense storm cells. South winds are forecast to increase to 15-20 kts this morning, with gusts reaching 25-30 kts. Low-level wind shear is anticipated late tonight at regional terminals as 50 kt southwest winds return aloft. An additional round of thunderstorms will move in from the west overnight before sunrise; a PROB30 group has been added to address this potential. && .ILX WATCHES/WARNINGS/ADVISORIES... None. && $$ KEY MESSAGES...MJA DISCUSSION...MJA AVIATION...MJA  036 FXUS66 KSGX 181042 AFDSGX Area Forecast Discussion National Weather Service San Diego CA 342 AM PDT Mon May 18 2026 .SYNOPSIS... High temperatures the coast to the coastal slopes of the mountains will warm several degrees today with faster inland clearing of night and morning coastal low clouds today and Tuesday. Warming will expand into the deserts on Tuesday and continue on Wednesday as the coast and valleys begin to cool on Wednesday. Not much change in high temperatures for Thursday through Sunday with high temperatures a few to around 5 degrees above average. A more persistent coastal eddy will bring greater coverage of night and morning coastal low clouds for the middle of the week with low clouds spreading into the western valleys for early Wednesday and into the inland valleys for early Thursday. && .DISCUSSION...FOR EXTREME SOUTHWESTERN CALIFORNIA INCLUDING ORANGE... SAN DIEGO...WESTERN RIVERSIDE AND SOUTHWESTERN SAN BERNARDINO COUNTIES... .SHORT TERM (Today through Wednesday)... Northwest to north winds for the mountains and deserts will become north to northeast this morning, then diminish through the afternoon. High temperatures for the deserts will be a few degrees cooler today. High temperatures for the coast to the coastal slopes of the mountains will warm several degrees today, as much as 10 to 15 degrees for the Inland Empire. There will be warming for most areas on Tuesday with high temperatures as much as 5 to 10 degrees warmer for the mountains, deserts, and inland valleys. For Wednesday, the coast and valleys will begin to cool while high temperatures for the mountains and deserts warm another few to around 5 degrees. While a weak coastal eddy will continue at times through Tuesday, mainly nights and early mornings, low clouds should clear faster for inland areas, especially on Tuesday. However, the local NAM- bounded WRF shows a more persistent coastal eddy developing Tuesday night and continuing into Thursday with more widespread coastal low clouds spreading into the western valleys for Tuesday night into Wednesday morning and into the inland valleys for the Wednesday night into Thursday morning as the marine layer deepens. && .LONG TERM (Thursday through Sunday)... There will be slight day-to-day differences in high temperatures for Thursday through next weekend with high temperatures a few to around 5 degrees above average. High temperatures will range from around 70 near the coast to the 80s for the Inland Empire with the lower deserts around 100. && .AVIATION... 180930Z...Coast/Valleys...Low clouds with varying bases 2000-4000 feet MSL will scatter out from northeast to southwest this morning by 16Z. Low confidence in the return of low clouds this evening, but areas should return mainly vcnty KSAN after 03Z. Any cigs would be based around 1500 feet MSL and intermittent. Mountains/Deserts...Offshore northerly winds will bring gusts 25-35 knots through and below mountain passes through 20Z. Pockets of LLWS and downdrafts in lee (south and west) of mountains. && .MARINE... No hazardous marine conditions are expected through Friday. && .BEACHES... Surf up to 5 feet this morning will gradually fade during the day. Elevated surf could combine with high tides this morning to produce minor tidal overflow. See the Coastal Hazard Message for details. && .SKYWARN... Skywarn activation is not requested. However weather spotters are encouraged to report significant weather conditions. && .SGX WATCHES/WARNINGS/ADVISORIES... CA...Beach Hazards Statement until 9 AM PDT this morning for Orange County Coastal Areas-San Diego County Coastal Areas. Wind Advisory until 3 AM PDT early this morning for Apple and Lucerne Valleys-Riverside County Mountains-San BernardinoCounty Mountains-San Diego County Deserts-San Diego County Mountains-San Gorgonio Pass near Banning. PZ...None. && $$ PUBLIC...17 AVIATION/MARINE/BEACHES...MM  091 FXUS62 KMLB 181044 AFDMLB Area Forecast Discussion National Weather Service Melbourne FL 644 AM EDT Mon May 18 2026 ...New AVIATION... .KEY MESSAGES... Issued at 148 AM EDT Mon May 18 2026 - Isolated to scattered shower and storm development is forecast each afternoon across east central Florida through this week. - A Moderate HeatRisk is forecast to gradually spread across east central Florida late week and into the weekend due to warm temperatures; adequate hydration and breaks from the heat will be important for those spending extended periods of time outdoors. - High risk for life-threatening rip currents continues at ALL central Florida Atlantic beaches today. Entering the dangerous surf is strongly discouraged. && .DISCUSSION... Issued at 148 AM EDT Mon May 18 2026 Today-Tonight...Ridging over the western Atlantic maintains a ridge axis north of Florida, across the Southeast US today. Easterly winds prevail, increasing to around 15 mph this afternoon as the sea breeze develops, with wind gusts 20-25 mph. Rain chances begin to increase slightly south of Orlando (20-30%), as PWATs build from <1" to up to 1.4-1.6" by late afternoon. However, a dominant east coast sea breeze will continue to keep the highest PoPs confined to the western half of the peninsula. While moisture increases today, lingering dry air in the mid- levels maintains DCAPE values near 900-1000 J/kg across southern portions of the forecast area. Therefore, though this will discourage updraft development overall, a few strong wind gusts near 50 mph cannot be ruled out in any storms. 500 mb temperatures near -10 C could also lead to small hail. Peak chances will occur this afternoon, though a few to scattered showers and a storm or two will remain possible along the coast overnight as cells develop over the Atlantic and drift onshore, mainly along the Treasure Coast. Highs in the upper 80s along the coast rise into the lower 90s over the interior. Warm overnight lows in the 70s will remain near 80 along the coast. Tuesday-Monday...High pressure remains off of the eastern US seaboard through the weekend and into early next week. The ridge axis remains well north of Florida, helping to fend off a cold front mid to late week. Meanwhile, an upper level low lingers near to north of the Bahamas. It's essentially a persistence forecast through the period, as onshore flow continues to prevail. The only changes are a slight shift to predominantly SE flow from E this weekend and an increase in moisture during the same timeframe. Therefore, expect isolated to scattered showers and storms each day through the end of the work week. A prevailing easterly sea breeze will increase winds to around 15 mph each afternoon, with gusts 20-25 mph. The daily sea breeze collision will favor the far interior, if not western half of the peninsula. Thus, that is where the highest rainfall chances are for the afternoons and into the evening hours. However, could see overnight showers and perhaps a storm drift onshore each night, mainly along the Treasure Coast, as they develop over the Atlantic waters. Lingering drier air in the mid-levels will inhibit updraft development, but could lead to a few strong wind gusts (~50 mph) in any storms that manage to develop, especially along the collision. Models are in good agreement that a slug of moisture (PWATs 1.7-1.8") will overspread the peninsula along SE flow late in the period. PoPs respond accordingly, increasing from 30-50% to 50-70% for Memorial Day Weekend. However, still plenty of time to watch how things unfold. Regardless, high temperatures remain in the upper 80s to near 90 this week, while onshore flow keeps lows in the 70s, possibly near 80 along the immediate coast. && .MARINE... Issued at 148 AM EDT Mon May 182026 High pressure remains offshore from the eastern US coast through the work week, with the ridge axis well north of the local area. Thus, onshore flow will continue through the period, increasing to around 10-15 kts each afternoon behind the sea breeze. Generally favorable boating conditions, with the exception of this evening into Tuesday morning, when winds across the offshore waters increase to 15-20 kts and seas build to 5 ft. Otherwise, seas 2-4 ft. Isolated to scattered showers and storms are forecast each day, though onshore flow will prevent any drift back towards the east coast. Instead, the best chances for the Atlantic waters are expected during the evening and overnight hours, when cells may occasionally drift onshore. && .AVIATION... (12Z TAFs) Issued at 644 AM EDT Mon May 18 2026 Mostly VFR. A few showers are observed in vicinity of SUA early this morning, but otherwise quiet. East winds become breezy behind the sea breeze into this afternoon increasing to 12-15 kts with locally higher gusts. Inland TAF sites should remain dry, and the best chances for coastal showers remains at FPR/SUA. && .FIRE WEATHER... Issued at 148 AM EDT Mon May 18 2026 High pressure remains over the western Atlantic through this week, with the ridge axis well north of the local area. Onshore flow will prevail, increasing to 10 to 15 mph, with gusts 20 to 25 mph, each afternoon behind the sea breeze. Isolated to scattered showers and storms are forecast each afternoon, with moisture increasing into the weekend. While onshore flow will keep most of the area well above any RH concerns, min RH west of Orlando could fall to between 45 to 50% during the heat of the day through much of the work week. Conditions will be fire sensitive in the afternoons, due to breezy winds and occasional lightning strikes. && .PRELIMINARY POINT TEMPS/POPS... DAB 87 75 87 74 / 0 10 20 10 MCO 89 73 89 73 / 20 10 30 0 MLB 86 77 86 77 / 20 20 20 10 VRB 86 76 87 76 / 30 20 30 10 LEE 91 72 90 72 / 10 0 30 0 SFB 90 73 89 72 / 10 10 30 0 ORL 90 73 89 73 / 10 10 30 0 FPR 86 76 86 75 / 30 20 30 10 && .MLB WATCHES/WARNINGS/ADVISORIES... FL...None. AM...None. && $$ DISCUSSION...Wishard AVIATION...Law  090 FXUS63 KILX 181044 AFDILX Area Forecast Discussion National Weather Service Lincoln IL 544 AM CDT Mon May 18 2026 .KEY MESSAGES... - There is a Slight Risk (level 2 of 5) for severe weather areawide today. While all severe weather hazards will be possible, damaging wind gusts in excess of 60 mph will be the most likely. - Additional thunderstorms will develop along an advancing cold front on Tuesday, with a Slight Risk (level 2 of 5) for severe weather in areas east of Interstate 55. Once again, damaging wind gusts in excess of 60 mph will be the most likely hazard. && .DISCUSSION... Issued at 543 AM CDT Mon May 18 2026 ...Active Convective Complex This Morning... Radar analysis early this morning reveals a robust linear Mesoscale Convective System (MCS) stretching from north-central Wisconsin down through southeast Iowa, central Missouri, and into eastern Kansas. Strong, consolidating cold pools have allowed a leading outflow boundary to outrun the primary convective line. Convective-allowing models (CAMs) exhibit high confidence that this system will maintain its structural integrity as it pushes eastward into the central Illinois forecast area later this morning. Sustaining this morning activity is a potent 40-50 kt low-level jet (LLJ) parked directly over central Illinois. This feature, working in tandem with subtle mid-level shortwaves embedded within the southwest flow aloft, is providing ample synoptic lift and elevated instability (MUCAPE around 1500 J/kg). While weak deep- layer shear (> 30 kts) should keep the morning activity largely disorganized and sub-severe, mid-level dry air and localized evaporative cooling could help overcome the waning morning inversion, supporting isolated severe hail or localized downburst winds. As an interesting aside, numerous runs of the HRRR overnight depicted an area of 40-50 kt surface winds within the trailing stratiform region, in an otherwise unassuming area. While it is uncertain if the model is resolving a wake-low or meso-high feature, the trend bears close observation. If these winds materialize, a short- fused wind advisory or high wind warning may become necessary for a brief window this afternoon. ...Severe Potential This Afternoon... By early afternoon, attention shifts to areas near and east of a Taylorville-to- Champaign line. A compact shortwave trough is progged to lift northeastward out of southeast Missouri around 18z, enhancing background kinematic shear and dynamic forcing across a highly buoyant boundary layer. In this zone, temperatures climbing toward the 80-degree mark and dewpoints hovering near 70 degrees will yield SBCAPE values exceeding 2000 J/kg. While the incoming shortwave will likely spark an increase in convective coverage ahead of the main morning line, individual storm intensity remains somewhat conditional. An important limiting factor is that mid-level lapse rates will likely deteriorate through the afternoon as the residual Elevated Mixed Layer (EML) exits to the east. However, as deep- layer shear ticks upward across southeast Illinois later today, localized enhancements within the main convective line remain a possibility. This could yield bowing segments capable of producing the full spectrum of severe weather hazards as the line advances into the southeastern counties. The severe threat will not completely diminish after dark. Additional shortwaves interacting with the persistent 40-50 kt LLJ core will likely sustain elevated convective development ahead of the approaching cold front well into Tuesday morning. ...Conditional Severe Threat on Tuesday... Significant forecasting uncertainty shrouds the Tuesday period, primarily driven by nebulous synoptic forcing and the likelihood of extensivemorning convective debris. If widespread cloud cover and rain persist deep into the morning hours, afternoon destabilization will be severely limited, rendering the severe weather threat highly conditional. At this juncture, the highest probability for boundary layer recovery exists near and south of the Interstate 72 corridor, extending through southeast Illinois ahead of the advancing cold front. Should adequate destabilization manifest, favorable instability and deep-layer shear profiles would initially support discrete supercellular structures. However, because the regional shear vectors are oriented nearly parallel to the surface frontal boundary, any discrete activity is expected to transition rapidly into a linear MCS as the front sweeps through Tuesday evening. ...Hydrological Concerns and High QPF Variability... Confidence remains exceptionally high that multiple rounds of convective rainfall will impact the entire region through Tuesday evening. However, the complex, repeated nature of this pattern introduces severe spatial discrepancies in expected precipitation totals. 48-hour HREF Localized Probability Match Mean (LPMM) QPF projections valid through 00z Wednesday demonstrate a stark variance, showing localized pockets picking up a mere quarter-inch while repeating strom cores could exceed 4.5 inches. Current model guidance continues to pinpoint the highest risk for these excessive, flood-producing rainfall totals along and south of the I-72 corridor, where repeated convective elements are most likely to anchor. ...Midweek Clearing Followed by a Wet Weekend Outlook... Wednesday through Thursday: A welcome pattern shift occurs mid- week as a cooler, significantly more stable post-frontal regime takes hold. Continental high pressure building into the Midwest will clear skies and lower humidity levels, offering a brief reprieve from the active weather. Friday through Sunday: The dry spell will be short-lived. Global deterministic models are in notably better agreement, signaling a return to a wetter, unsettled pattern by late week. As the surface high pressure slants eastward, a potent mid-level shortwave will advance across the central U.S. A steady plume of Gulf moisture combined with a series of minor shortwave impulses lifting northeast from the Southern Plains will keep central Illinois susceptible to multiple rounds of scattered showers. While weak kinematic profiles should heavily restrict the overall severe weather risk, a gradual build-up of instability over the weekend will support widespread thunderstorm development. && .AVIATION /12Z TAFS THROUGH 12Z TUESDAY/... Issued at 519 AM CDT Mon May 18 2026 A line of thunderstorms approaching from the west is expected to reach KPIA by 13Z, KSPI and KBMI by 15Z, and KDEC/KCMI by 16Z this morning. A three-hour TEMPO group has been included to account for IFR visibilities during the storms, with scattered showers likely to linger for several hours afterward under generally VFR conditions. Brief periods of degraded conditions are possible within the most intense storm cells. South winds are forecast to increase to 15-20 kts this morning, with gusts reaching 25-30 kts. Low-level wind shear is anticipated late tonight at regional terminals as 50 kt southwest winds return aloft. An additional round of thunderstorms will move in from the west overnight before sunrise; a PROB30 group has been added to address this potential. && .ILX WATCHES/WARNINGS/ADVISORIES... None. && $$ KEY MESSAGES...MJA DISCUSSION...MJA AVIATION...MJA  211 FXUS61 KGYX 181046 AFDGYX Area Forecast Discussion National Weather Service Gray ME 646 AM EDT Mon May 18 2026 .WHAT HAS CHANGED... Further raised PoPs across central and northern NH this morning based on upstream precipitation on latest radar mosaic. This incoming activity has had some lightning with it, so have also put in a slight chance of thunderstorms in central and northern NH. && .KEY MESSAGES... 1. Cooler today in ME with southeasterly winds, but still very warm across much of NH. A few showers possible this morning in central and northern NH including the western ME mountains. 2. Tuesday and Wednesday should feature the warmest temperatures of the year thus far with chances of isolated to scattered thunderstorms, some potentially strong. 3. Expect cooler and dry conditions to end the work week with temperatures around or slightly below normal for this time of year through the weekend. && .DISCUSSION... KEY MESSAGE 1 DESCRIPTION... High pressure will slide offshore early this morning allowing SFC winds to have an easterly component going through the day today. With ocean temperatures still in the 40s, most Maine zones outside of the mountains should be a good deal cooler today. Temperatures will continue to be quite warm in much of NH as the ocean will obviously have lesser of a cooling influence. A modest burst of WAA aloft will aid in a chance for showers across central and northern NH this morning, with perhaps even a rumble of thunder will relatively steep lapse rates aloft. This activity should lift northeastward into the western ME mountains and foothills by late morning then dry out. The rest of the forecast area should remain dry. Showers and perhaps a few rumbles of thunder may affect northernmost NH and the western ME mountains tonight but the bulk of the activity should remain in Canada as warm front returns northward there. KEY MESSAGE 2 DESCRIPTION... A progressive low amplitude shortwave trough will pass north of the forecast area on Tuesday, flattening the ridge a bit and leading to some modest height falls. A band of mid-level westerlys in the 40 to 50 knot range will spread across the region through early afternoon, which could lead to some early day storms in the vicinity of the southern Kennebec Valley and portions of the Midcoast. A second wave will approach New Hampshire late afternoon or early evening. Storms may be ongoing over Vermont before moving into New Hampshire and we could also have some additional development over the mountains. In both potential storm regimes, storm coverage remains uncertain given nebulous forcing mechanisms and less than ideal diurnal timing (early in the day for the eastern storms and closer to evening for the western/northern storms). All in all, both environments could see CAPE values in the 500 to 1000 J/kg range and deep layer shear up to 35 knots or so. Thus, any storms that do form could become strong or marginally severe with the primary threats of small hail, gusty winds, and frequent lightning. Showers and storms should diminish mid to late evening. A cold front will move across the area of Wednesday and guidance has continued the trend of speeding that passage up. In fact, the NAM almost has the front around the Midcoast by 18z. So, we do have a risk for some stronger storms earlier in the day on Wednesday along and ahead of the front but the window will be short before the boundary moves out over the waters. Tuesday and Wednesday will also be the warmest days of the year thus far with widespread highs in the 80s and potentially even in the lower 90s. Tuesday's highs will range from the upper 70s and lower 80s north, to the upper 80s and lower 90s south. Coastal areas may be a little bit cooler given an onshore wind component. Wednesday will be a touch cooler for most with the passage of the cold front. We will still see widespread highs in the low to mid 80s along and south of the Foothills. Temperatures over the higher terrain will max out in the lower 60s to low/mid 70s. KEY MESSAGE 3 DESCRIPTION... We will cool down behind the front through the rest of the work week and into the weekend. The coolest day will be on Thursday when highs will mainly range from the low to mid 50s north, to the low to mid 60s south. We warm just slightly on Friday and temperatures generally stay around or slightly below normal through the weekend. The weather pattern also favors dry conditions during this time frame. && .AVIATION /06Z MONDAY THROUGH FRIDAY/... Through 12z Tuesday...Mainly VFR today with the exception of possible MVFR restrictions at HIE and LEB with showers and isolated thunderstorms approaching from the west this morning. VFR tonight for most locations. However, with low level easterlies we may see some MVFR to IFR restrictions in fog or low stratus, especially on the coastal plain. LLWS is also possible overnight tonight. Outlook: Tuesday: Afternoon SHRA/TS chances near the US/CAN border. There is uncertainty how far east and south SHRA/TS develop in the afternoon. Tuesday night: Coverage of SHRA decreases. VFR forecast. Wednesday: A cold front passes through the region with SHRA/TS west to east through the day. MVFR possible w/ frontal passage and in showers/storms. Wednesday night: Winds shift NW with VFR behind exiting cold front. Thursday and Thursday night: VFR expected with no sig wx. Friday and Friday night: VFR expected with no sig wx. && .MARINE... High pressure moves over the waters today with relatively light easterly to southeasterly winds. Winds may approach SCA criteria on the coastal waters Tuesday and Wednesday as southerly fetch builds. Winds then become offshore behind a stronger cold front Wed evening. High pressure builds in from the west mid to late week. && .GYX WATCHES/WARNINGS/ADVISORIES... ME...None. NH...None. MARINE...None. && $$ DISCUSSION...Combs/Ekster/Hargrove  224 FXUS64 KHGX 181047 AFDHGX Area Forecast Discussion National Weather Service Houston/Galveston TX 547 AM CDT Mon May 18 2026 ...New AVIATION... .KEY MESSAGES... - Warm, breezy, and muggy conditions will continue for the next several days. - Isolated showers/storms possible overnight, isolated to scattered showers/storms on Monday, followed by increasing chances of showers and storms for the rest of the week. - Multiple rounds of showers/storms expected beginning late Tuesday through the end of the work week. A few storms could be strong to severe and multiple rounds of rainfall could lead to minor/street flooding. - Elevated winds, seas, tides, and rip current risk in the bay/Gulf waters and beaches through at least midweek. && .DISCUSSION... Issued at 1212 AM CDT Mon May 18 2026 I'm gonna go ahead and lead in with the main takeaways for this discussion: have an umbrella/poncho with you throughout the week, remain weather aware by staying up to date on the latest forecasts, and have multiple ways to receive alerts of impactful weather. That's your big three for this week. A band of showers is setting up over Central Texas and is gradually pushing into Southeast Texas this evening. PW values remain well above the 90th percentile (~1.79") and when you pair that with a strengthening LLJ (30-40 kt) and embedded shortwaves, you get *vaguely gestures at radar reflectivity* that. Some of the latest 00Z CAM guidance indicates the potential for isolated embedded thunderstorms overnight as well. Based on the instability and lifting mechanism in place (the LLJ), this is an entirely plausible outcome (and not only because it's already occuring). This is most likely to occur near or north of I-10 during the overnight hours, so don't be surprised if you wake up before your alarm to some rumbles of thunder...Happy Monday! Monday will feature isolated to scattered showers with a non-zero chance of an isolated storm or two in the afternoon mainly north of I-10. Outside of the rain chances, it's gonna be warm and muggy. High temperatures will continue to top out in the upper 80s to low 90s with heat index values peaking in the upper 90s/low 100s. A rinse and repeat for Tuesday, but definitely more so on the rinse part of that as we head into late Tuesday. The wet pattern that we're moving into Tuesday and beyond is courtesy of a longwave trough that is becoming established over the western CONUS. Southwesterly flow aloft will lead to embedded shortwaves passing through the area with the first notable one being on late Tuesday. Exact timing is still uncertain (as always when trying to time shortwaves), but we're currently looking at Tuesday evening for the first round of showers/storms. This shortwave is expected to result in a line of showers/storms, or if you want to be fancy you can call it a Mesoscale Convective System (MCS) that pushes into the area on Tuesday evening. A few of these storms could be strong to severe and be capable of producing strong wind gusts and hail. As a result, majority of Southeast Texas is outlined in a marginal risk (level 1 of 5) of severe weather on Tuesday. The severe weather outlook may change with the overnight update, so be sure to stay tuned to the forecast. The line of storms is visible at the very end of 00Z CAMs and we can see convection beginning to approach the Brazos Valley right around 7pm Tuesday evening. Additional rounds of showers and thunderstorms are anticipated throughout the week with the most likely mechanism being more MCS's especially along a nearby frontal boundary that makes its closest approach around midweek. Where this boundary lingers/stalls will be key to who gets the most amount of rainfall this week. With PW values remaining near or above the 90th percentile, locally heavy rainfall will be possible. There is additional details down below in the Hydrology section. A brief summary of it is, the rounds of rain earlier in the week will help to prime the soils. This means that rounds of rain later in the week could result in a quicker transition to runoff which increases the potential for minor/street flooding. We've already seen in recent events over the past few weeks that PW values in this range can result in 3-4+"/hr rainfall rates in the heaviest downpours. As a result, all of Southeast Texas is outlined in a marginal risk (level 1 of 4) Tuesday through at least Thursday. I say at least because with rain chances sticking around into the weekend, there is decent potential that at least portions of the area will remain outlined in the Excessive Rainfall Outlook. Speaking of Thursday, a portion of the Brazos Valley is outlined in a slight risk (level 2 of 4) of excessive rainfall on Thursday. Training convection along the lingering frontal boundary cannot be ruled out. Be sure to stay tuned to the forecast for the latest details. As far as rainfall totals go, we continue to anticipate widespread totals of 2-4" with isolated amounts of 4-6+". This is for the Tuesday through Friday timeframe, and those higher end amounts are still most likely to occur north of I-10. The frontal boundary continues to linger going into the weekend alongside a steady dose of passing shortwaves and elevated PW values, so chances for showers/storms continue going into the weekend. With daily chances for moderate to heavy rainfall, we'll be keeping an eye on area rivers/streams...that's another hint to check out the Hydrology section below. In case you wanted to know more about the temperature forecast, there's a downward trend going into midweek with the increasing rain chances (surprise surprise). We go from high temperatures in the upper 80s/low 90s on Monday and Tuesday to the low to mid 80s midweek and beyond. The temperature forecast will likely change based on timing and location of these rounds of showers/storms. I( can mention though that we'll at least flirt with record high minimum temperatures early this week with low temperatures only bottoming out in the upper 70s/low 80s. Yeah...some of y'all might not drop below 80 overnight. Now that's what I call humid! Batiste && .AVIATION... (12Z TAF Issuance) Issued at 543 AM CDT Mon May 18 2026 Widespread MVFR cigs should generally trend VFR this morning. Coastal areas may struggle break out of MVFR cigs, but perhaps a brief period of VFR could occur this afternoon like yesterday. Winds will continue to be gusty and out of the southeast. Sustained winds are expected to average in the 15-20 knot range, with gusts over 25 knots expected in some areas. Cigs should trend back to MVFR by evening and overnight. && .MARINE... Issued at 1212 AM CDT Mon May 18 2026 Small Craft Advisories remain in effect through Tuesday morning as moderate onshore winds and elevated seas continue to persist. Winds and seas gradually subside on Tuesday. Multiple rounds of showers and thunderstorms are anticipated beginning late Tuesday through at least the end of the work week. Some of these storms could produce strong wind gusts, especially if they push offshore in the form of a line of storms. Outside of the storms, onshore winds will persist generally in the 10-15 kt range after Tuesday. The other topic of interest for mariners is the continued high risk of rip currents and potential for minor coastal flooding during times of high tide. Water levels at Galveston Bay Entrance reached 3.3 ft MLLW during high tide on Sunday morning. P-ETSS guidance continues to indicate water levels being slightly higher than that during high tide Monday morning peaking closer to 3.5 ft MLLW. Water levels during high tide on Tuesday morning are currently expected to peak just above 3.0 ft MLLW. A Beach Hazards Statement remains in effect through Monday morning and will transition to a Rip Current Statement afterwards through Tuesday evening (for now). Expect the rip current risk to remain high through at least midweek. Batiste && .HYDROLOGY... Issued at 1212 AM CDT Mon May 18 2026 Anticipating multiple rounds of moderate to heavy rainfall Tuesday through at least Friday. These rounds are expected to mostly be in the form of Mesoscale Convective Systems (MCS's). The exact timing of these storms can be a bit tricky as mesoscale factors play a key role (hence the name), but we anticipate the first round to come late Tuesday. With PW values near or above the 90th percentile (~1.79"), rainfall rates will likely exceed 3-4"/hr in the heaviest downpours. While these lines of storms are typically progressive, the rainfall received early in the week is expected to prime the soils for rounds later in the week. Saturated soils leads to a quicker transition to runoff which brings an increased risk of minor/street flooding. We continue to anticipate widespread rainfall totals of 2-4" with isolated higher amounts (4-6+" possible). The highest rainfall totals are still expected to occur north of I-10. This rainfall will generate runoff and cause rises on area rivers and watersheds. Action to minor stage flooding is the most likely outcome, but cannot entirely rule out isolated instances of moderate stage flooding depending on where the most rainfall accumulates. Remember that you can monitor updated river forecasts via the NWS NWPS webpage (https://water.noaa.gov/). Batiste && .PRELIMINARY POINT TEMPS/POPS... College Station (CLL) 90 78 89 72 / 10 20 60 70 Houston (IAH) 89 79 89 75 / 20 10 40 70 Galveston (GLS) 86 81 86 79 / 20 10 20 60 && .HGX WATCHES/WARNINGS/ADVISORIES... TX...Beach Hazards Statement until 10 AM CDT this morning for TXZ436>439. High Rip Current Risk from 10 AM CDT this morning through Tuesday evening for TXZ436>439. GM...Small Craft Advisory until 9 AM CDT Tuesday for GMZ330-335-350- 355-370-375. && $$ DISCUSSION...Batiste AVIATION...Self MARINE...Batiste  254 FXUS61 KCTP 181048 AFDCTP Area Forecast Discussion National Weather Service State College PA 648 AM EDT Mon May 18 2026 .WHAT HAS CHANGED... * Collaborated with WFO LWX and SPC to increased POPs for pulse/multicell TSRA with the potential for gusty winds later this afternoon and evening across Scent PA and the West Br Susq Valley. SPC painted a MRGL Risk for SVR across that area of the CWA. * Also slightly expanded the low pops for SHRA/TSRA Tuesday afternoon and evening and included the potential for gusty wind and hail. && .KEY MESSAGES... 1) Hottest temperatures of the year so far forecast this afternoon and Tuesday with highs pushing into the 80s and 90s. 2) A strong cold front to bring showers and thunderstorms with the potential for severe weather on Wednesday followed by colder temperatures. && .DISCUSSION... KEY MESSAGE 1: Hottest temperatures of the year so far forecast this afternoon and Tuesday with highs pushing into the 80s and 90s. An extensive, but rather thin veil of high clouds covering much of the CWA early today will help to create near optimal conditions for a surge in heat today, thanks in part to their blanketing effect to reduce radiational cooling overnight and their minimal impact on insolation today. Temps will start the daylight hours in the 60s in most locations. Daytime high temperatures will be steadily rising today through Tuesday as an anomalous upper level ridge amplifies over the Eastern U.S. This will help to create very warm to hot, summerlike conditions centered on this afternoon and Tuesday afternoon. 500 mb heights per the GEFS rise about 120 dam from Sunday morning to late Monday with standardized anomalies of these heights reaching over +2 sigma along the Mid Atlantic Coast 18Z Monday through 18z Tuesday. Collaborated with LWX and SPC to paint a MRGL risk for SVR TSRA from the Scent Mtns to the West Branch Valley of the Susq near the eastern edge of somewhat stronger (35-40 kt) swrly mid level winds with MU CAPE reaching near 2000 J/KG. Additionally, the eastern edge of an elevated mixed layer (currently over the Middle Ohio River Valley) will be tracking ENE at 15-20 kts and reach the western edge of the MRGL Risk area around 22-23Z today helping to enhance mid level lapse rates and updraft intensity. Mentioned the potential for gusty winds associated with the the clearly high-based convection occurring within an inverted-V sounding. High temperatures will peak in the mid 80s to mid 90s this afternoon based on elevation and proximity to the best llvl downslope and enhancement by adiabatic warming via the light southwesterly breeze today and moderately gusty WSW wind on Tuesday (with gusts in the 15 to 20 mph range during the late morning and afternoon hours). Daily record highs could be challenged in some locations. See the Climate section for more details. Manual adjustments were made to lower NBM maxT by a few degrees today due to a known systematic bias correction issue identified during the shoulder seasons. This should also keep max heat indices under 100F, precluding any need for Heat Advisories. Still, heat risk impacts will continue to be monitored given the quick ramp-up in heat and limited acclimation time. Dewpoints over 60F for many will also feel more humid relative the recent cool stretch we've had. With a boundary just to our north and sufficient instability in the warm sector over PA, there will be a chance for additional stray afternoon and early evening showers or thunderstorms this afternoon, with a better chance for locally robust convection on Tuesday across the Northern half of PA. Most places stay dry though, but thunderstorms could drop a quick 0.10 to 0.25" of rain in any one location. ------------------------------------------------------------- KEY MESSAGE 2: A strong cold front to bring showers and thunderstorms with the potential for severe weather on Wednesday followed by colder temperatures. A cold front (accompanied by more widespread and frequent showers/t-storms) brings relief to the relatively short bout of heat and moderate humidity Wednesday into Thursday. DOD max temp drop from Tuesday to Wed will be 20 deg F or greater in most locations. Some of the AI guidance paints an elevated risk of severe weather across the Lower Susquehanna Valley on Wednesday afternoon in the presence of peak heating and sufficient shear/CAPE profiles. The magnitude & location of the severe threat will be highly dependent on cold front passage timing and amount of cloud cover in advance of the frontal boundary. The eventual risk area will highlight locations along and downstream of the cold front between 12PM and 8PM on Wednesday. In the wake of the cold front, high pressure will build in for a short time. Temperatures are forecast to cool down back to historical/climo averages for late May for the end of next week. Early indications show the aforementioned cold front stalling out south of the Mason-Dixon line late in the week and lifting back north across PA as a warm front into Memorial Day weekend. The current outlook favors a cooler/wetter stretch through the holiday weekend thanks to that warm front, but there is still a lot of time for the forecast to trend in a more favorable and optimistic direction for the holiday weekend that marks the unofficial start of summer. && .AVIATION /12Z MONDAY THROUGH FRIDAY/... Patchy fog/mist will erode this morning as sunshine mixes out the boundary layer, with VFR expected to prevail outside of where gusty showers/thunderstorms develop later this afternoon and evening. Convective-allowing models (CAMs) are signaling at convective initiation across the Mid-Atlantic later in the afternoon via low-level convergence associated with a lee trough across the Mid-Atlantic + upper-level support in the right entrance region of a subtle 40-kt jet streak. Although pronounced ridging across the East Coast will tend to suppress convective activity, a few showers/thunderstorms cannot be ruled out. Given the moderately unstable environment (HREF mean SBCAPE around 1500-2000 J/kg), inverted-V profiles in place (surface T/Td spreads around 15C with DCAPE values in excess of 1000 J/kg), and low-moderate wind shear (around 30 kts) primarily within the lowest 3 km, outflow- dominant cell clusters with locally gusty winds are the favored storm mode. Given the weak forcing mechanisms in place + storm coverage uncertainties, mentions were limited to PROB30 groups at this time. Activity is expected to diminish after sunset as forcing weakens due to loss of daytime heating. Otherwise, VFR is expected to prevail outside of convection. Overnight, a shortwave tracking across the Great Lakes may result in a few showers/thundershowers across West-Central PA (mainly KBFD), though flight restrictions appear unlikely with this activity. Outlook... Tue...Mainly VFR. Patchy A.M. fog possible. Isolated P.M. shower or t-storm possible. Wed...Restrictions probable through Wednesday night with widespread showers/storms along CFROPA. Thu...Lingering showers across S PA, restrictions possible. Fri...Lingering showers across S PA, restrictions possible. && .CLIMATE... Daily record max temperature for May 18-19: 5/18 5/19 Harrisburg 94 in 1962 95 in 1962 Williamsport 95 in 1962 96 in 1996 Altoona 91 in 1962/1996/2017 92 in 1996 Bradford 85 in 1962 85 in 1962 State College 92 in 1962 92in 1934/1996 Overnight low temperatures on Monday night into Tuesday are also in jeopardy. Please note: State College Co-operative observations are a 24-hour summary taken once per day around 7 AM (7AM-7AM). Therefore, a max temp occurring in the daylight or late in the day is usually reported in the _next_ day's observation. Also, the same min temp may be reported on two consecutive days if the min occurs at observation time. && .CTP WATCHES/WARNINGS/ADVISORIES... None. && $$ WHAT HAS CHANGED...Lambert/Banghoff/Martin KEY MESSAGES...Lambert/Banghoff/Martin DISCUSSION...Lambert/Banghoff/Martin AVIATION...Teare CLIMATE...Dangelo/Steinbugl  247 FXUS63 KGRR 181048 AFDGRR Area Forecast Discussion National Weather Service Grand Rapids MI 648 AM EDT Mon May 18 2026 .KEY MESSAGES... - Slight Risk for Severe Storms Today - Slight Risk for Severe Storms on Tuesday - Drier and cooler mid to late week && .DISCUSSION... Issued at 400 AM EDT Mon May 18 2026 - Slight Risk for Severe Storms Today The storm prediction center has placed Southwest Lower Michigan in a slight risk for severe weather today. Clouds and showers will try to press in from the west this morning which will decrease somewhat how much we can destabilize. 500mb flow will be weakening as we move through the day as well which is another negative factor with regard to severe weather chances. What we are watching though is the chance that the current activity redevelops or regenerates over our area after about noon (this is seen in the HREF). We feel that between roughly 100pm and 700pm there is chance for severe weather, especially south and east of a line from Whitehall to Clare (so the bulk of the area). An item of note in the HREF is the 850mb low level jet ramps up during the afternoon to 40-45 knots. The LLJ increase is seen most for areas near and southeast of GRR including AZO, LAN and JXN. These areas stand the best chance at some damaging winds this afternoon and evening. The Nadocast machine learning website also sees wind as our biggest threat today over our southeast half of the forecast area. There is a chance for some scattered storms tonight, but nothing that looks widespread. - Slight Risk for Severe Storms on Tuesday Another slight risk for severe storms is in place for Tuesday over the southeast CWA. The setup is similar in that decaying showers and storms will move in during the morning with a threat of redevelopment over our area in the afternoon. Tomorrow's threat though looks more confined to the southeast CWA, essentially a smaller threat area including AZO, LAN and JXN. Today we have some threat outside of those areas, but tomorrow (Tuesday) the best chances may very much be confined to those areas. Deep layer shear on Monday is 25-35 knots and Tuesday that increases to 30-40 knots. So some storm organization is possible especially with Tuesday's threat. Again though, the morning clouds and showers may dampen our threat a bit. - Drier and cooler mid to late week The cold front will sweep through the forecast area Tuesday evening. Much drier air will invade from the north with PWAT values plummeting from 1.7 inches Tuesday morning which is off the chart for this time of year to less than 0.5 inches on Wednesday. It will be noticeably cooler with highs in the 60s Wednesday and Thursday. Wednesday night we are likely looking at frost across Central Lower Michigan. Another systems looks to bring some rain out towards Friday, but the models have had difficulty coming to a consensus. The trend though looks to be towards rain on Friday. && .AVIATION /12Z TAFS THROUGH 12Z TUESDAY/... Issued at 647 AM EDT Mon May 18 2026 Very little change in thinking from overnight. We are expecting a broken line of showers and thunderstorms to move into Western Lower Michigan between 14z and 17z. These will largely be in a weak state. Re-intensification will take place around 17z however with a line of showers and storms then expected to push eastward through the TAF sites. Have VCTS in the TAFs now, but we expect at least scattered activity to affect the TAF sites between 17z and 23z. All sites will largely stay VFR today outside of some brief reductions in visibility and ceiling associated with a storm affecting any one TAF site. Winds will ramp up considerably in the next hour or two (or by 13z to 14z), with SSW winds from 190-210 running at 15-30 knots much of the day. && .MARINE... Issued at 400 AM EDT Mon May 18 2026 We have extended the Small Craft Advisory both in time and areal extent. The SCA now runs through Tuesday for all zone. The southern two zones, south of Holland, begin tonight. Strong southerly winds will continue both today and Tuesday as we remain east of the cold front the bulk of that time. South winds of 15 to 25 knots look common with waves of 3 to 6 feet. The SCA may need to be extended into Tuesday night for a period of stronger northwest winds behind the cold frontal passage. && .GRR WATCHES/WARNINGS/ADVISORIES... MI...None. MARINE...Small Craft Advisory from 2 AM to 8 PM EDT Tuesday for LMZ844- 845. Small Craft Advisory until 8 PM EDT Tuesday for LMZ846>849. && $$ DISCUSSION...Duke AVIATION...Duke MARINE...Duke  301 FXUS61 KRNK 181050 AFDRNK Area Forecast Discussion National Weather Service Blacksburg VA 650 AM EDT Mon May 18 2026 .WHAT HAS CHANGED... Chance of rain likely later in the week with cold front passage. Aviation updated. && .KEY MESSAGES... KEY MESSAGE 1: Multiple opportunities for precipitation following the cold front on Wednesday. && .DISCUSSION... KEY MESSAGE 1: Multiple opportunities for precipitation following the cold front on Wednesday. The warming trend will continue until a cold front arrives Wednesday to briefly bring cooler temperatures and the start of a wet trend for the region. The center of a surface high pressure system over Bermuda will nudge a little eastward and permit an approaching cold front to reach our area. The cold front's arrival will likely be as early as Wednesday. The front will struggle to pass southward but will be forced back northward as a warm front due to the presence of a developing low in south- central CONUS. The meandering behavior of the front suggests a multi-day precipitation trend where pretty much the entire region will get daily chances of rain. This is excellent news in relation to the drought conditions we have been going through this Spring. Flood concerns are on the lower end as it would take several inches in an hour to lead to any flash flooding. In addition, the rainfall estimates for Wednesday and Thursday combined range between 0.5-1.0 inches at best. PWATs are projected to average around 1-1.5" from Wednesday onward so some storms that develop may have relatively heavy rainfall rates. The severe weather threat looks to be low for Wednesday and Thursday. CAPE, no doubt, will be plentiful with the warm and moist conditions but the wind shear will be better to the north with bulk shear of only about 25 knots over southwest VA. Lapse rates are also underwhelming given the presence of warmer air aloft due to a 850mb surface high off the Atlantic. Still, the shear may be enough to support some organized multicells and modeled skew-Ts suggest inverted V soundings so the threat of damaging wind gusts cannot be ruled out. As a side note, the cold front will have a large surface high pressure system behind it, centered over the Great Lakes as it passes to our north. It will briefly wedge into our mountains and provide a break in the warm temperatures with highs in the 60s and lower 70s by Friday. The wedge and temperature drop does not last since the warm front then moves north to return high temperatures back to the 70s to lower 80s. Dew points and PWATs take a short dip as well but recover by the weekend. The warm front will be back to our north by the weekend and with reinforced warm and moist temperatures, the chances of daily rainfall may continue into early next week. Model guidance also hints at another surface low moving northeast across the Midwest and sending another front through by this weekend. Confidence is highest for rain on Wednesday and Thursday and any rain chances following will be monitored in future forecasts. && .AVIATION /12Z MONDAY THROUGH FRIDAY/... Aside from possible reduced VSBY/cig at KLWB from any fog that forms, expect VFR conditions through the period. Some daytime cu near 5-6 kft could form at the mountain sites otherwise some cirrus is possible. Daytime winds mainly south to SW at 10kts or less then decreasing back by this evening. EXTENDED AVIATION OUTLOOK... High pressure will keep the weather quiet and conditions VFR through the beginning of the week outside of any river valley fog that may develop. This river valley fog may lead to some brief periods of restrictions due to lowering VSBYs at LWB. More widespread rain and scattered thunderstorms are expected for Wednesday with the approach of a cold front. Rain and storm chances and cloud cover linger through the end of the week with the system possibly stalling across the area. This may lead to sub-VFR conditions through the end of the work week. Note: Bluefield (KBLF) ASOS is currently experiencing a technical outage due to a major power supply failure. Replacement parts have been ordered. ETA of repair is currently unknown. AMD NOT SKED is being appended to its TAF. && .CLIMATE... Record-breaking heat is possible early next week. Here are the current records and our current forecast. Monday, May 18, 2026 Station Hi Max T Hi Min T Forecast High Roanoke 94 in 1962 69 in 1996 94 Lynchburg 93 in 1911 68 in 1894 93 Danville 93 in 1974 69 in 2015 94 Bluefield 87 in 1996 66 in 2015 86 Blacksburg 88 in 1911 61 in 2018 90 Tuesday, May 19, 2026 Station Hi Max T Hi Min T Forecast High Roanoke 96 in 1962 69 in 2022 94 Lynchburg 93 in 1962 66 in 2022 93 Danville 95 in 1962 69 in 1962 95 Bluefield 89 in 1911 66 in 1977 86 Blacksburg 91 in 1911 61 in 1938 90 && .RNK WATCHES/WARNINGS/ADVISORIES... VA...None. NC...None. WV...None. && $$ DISCUSSION...CG AVIATION...AB CLIMATE...RCS/AB  345 FXUS63 KARX 181051 AFDARX Area Forecast Discussion National Weather Service La Crosse WI 551 AM CDT Mon May 18 2026 .KEY MESSAGES... - Severe storm threat returns through the area today with primary concern for damaging winds and secondary concerns of large hail and isolated tornadoes. Higher confidence for severe storms and storm initiation lies southwest of the forecast area into central and southwest Iowa with storms weakening as they lift northeast through the evening hours. - Colder with showers for Tuesday with colder temperatures sticking around into the weekend. Low chance for some local areas to see Frost Tuesday and Wednesday nights. && .DISCUSSION... Issued at 316 AM CDT Mon May 18 2026 Morning Observations & Synoptic Setup Today: An upper level longwave trough over the Rocky Mountain West on GOES water vapor imagery loops, evidently amplifying in enhancement of meridional GOES-derived upper level jet streaks lee of the Rocky Mountains, causes cyclogenesis over the Central Plains and subsequent reinvigoration of low level moisture transport, resulting in a similar severe weather set up as Sunday for the Upper Mississippi River Valley through this evening into tonight. Low Level Capping Limiting Local, Widespread Confidence Today: While it remains quite moist in the low levels early this morning, GOES upper level water vapor imagery loops and derived upper level winds depict a meagerly zonal perturbation eradicating moisture from the local forecast area to the east, tied to the long bowing non-severe radar returns from southern Iowa through northern Wisconsin. High resolution model analyses (18.06/18.00Z) suggest 850mb/925mb drying persisting through the early afternoon before cyclogenesis along the lingering low level baroclinic boundary spanning from the Mid Missouri River Valley to the northeast, kinked by anticyclonic rotation over Minnesota, initiates low level moisture transport northeastward towards the forecast area. The local drier, warmer low level air will cause another capping inversion, inherently increasing dependence on northern extent of moisture return (i.e., warm front) through the forecast area today. Current, further limiting factors include diurnal timing close to sunset and deamplification of the upper level wave as it nears the Upper Mississippi River Valley through the afternoon, both decreasing confidence in northerly frontal transport. Summarily, the current temporal and resultant spatial window for convection to become surface based or even achieve sufficient forcing to access enhanced MUCAPE (2000+ J/kg) from steeper mid level lapse rates limits local confidence. Furthermore, high resolution soundings and spatial analysis of available shear magnitudes are messy, at best. Splotches of severe storm supportive shear values across the forecast area remain tied closer to the actual frontal boundary, from southwest to northeast Minnesota through the afternoon and evening, eventually coinciding into the nighttime hours when a local capping inversion is more likely. The two synoptic factors or scenarios that would increase local severe threat through today would be a stronger wave lifting north out of the Southern Plains this morning or limited eradication of low level moisture this morning. Severe Storm Potential Timing, Location, & Impacts Today: Current confidence for damaging winds as the main hazard primarily along southwestern peripheral counties in northeast Iowa potentially into bordering counties of southwest Wisconsin and southeast Minnesota with secondary hazards of large hail and isolated tornado(es) this evening into tonight. While all hinge on northern extent of return flow and warm front location, damaging wind concerns are more widespread into western and central Wisconsin given the rapid ejection of the trough causing quick storm motions of potentially 50+ kts. Colder with Patchy Showers Tuesday: Eventually the upper level trough axis traverses east through the forecast overnight into Tuesday morning, advecting light rain showers into early Tuesday morning with additional cumulus popcorn shower potential into the daytime from steepening low level lapse rates within a low level CAA regime. Quite chilly showers to boot with daytime highs in the mid 50s to 60s and confidence for 925mb/850mb temperatures dropping 15+ C from 19.00Z to 20.00Z. Colder & Mostly Dry Into The Weekend: The colder than normal temperatures expected to stick around the Upper Mississippi River Valley until the weekend due to lingering low level anticyclonic flow locking in advection from a Canadian Continental quasi-polar airmass situated over the northern Great Lakes. Current confidence in lowest temperatures Tuesday night may graze Frost headlines along western peripheral counties in southeast Minnesota as well as northern peripheral counties in central Wisconsin Tuesday and WEdnesday nights. && .AVIATION /12Z TAFS THROUGH 12Z TUESDAY/... Issued at 549 AM CDT Mon May 18 2026 VFR expected through much of the morning hours as MVFR ceilings remain well upstream into central Minnesota at 18.12Z TAF issuance, eventually attempting to flirt closer to the forecast area through today. Haven't accounted for potential but may be an impact through the late morning to early afternoon should low level saturation come to fruition. Subsequent storm chances increase from southwest to northeast this evening into tonight. Storms quickly progress from with damaging winds as main severe hazard and large hail/isolated tornadoes as secondary threats. Storms exit the area with frontal passage overnight into Tuesday morning. && .ARX WATCHES/WARNINGS/ADVISORIES... WI...None. MN...None. IA...None. && $$ DISCUSSION...JAR AVIATION...JAR  342 FXUS64 KEWX 181051 AFDEWX Area Forecast Discussion National Weather Service Austin/San Antonio TX 551 AM CDT Mon May 18 2026 ...New AVIATION... .KEY MESSAGES... - Low chance for a few showers and storms today. - Active weather pattern from mid-week through the upcoming Memorial Holiday weekend. Heavy rain at times could lead to localized flooding. && .SHORT TERM... (Today through Tuesday) Issued at 124 AM CDT Mon May 18 2026 Today will be another warm and muggy day under mostly cloudy to perhaps partly cloudy skies as moisture remains strewn across the area. Highs should generally top out in the low 90s north and upper 90s south. We should see more peaks of sun than we did on Sunday which in turn will give us heat indices or "feels like" temps close to 100 for many areas with heat indices above 105 possible across the Winter Garden and Rio Grande Plains. We also should have a stronger cap in place today but it's possible we could see a storm try to break it mainly in the late afternoon/evening, if it does we could see a burst of heavy rainfall along with the potential for small hail and gusty winds. If any activity does form it should wane significantly after sunset with the loss of daytime heating. Tuesday should be another warm and very muggy day as we remain entrenched underneath this southwest flow aloft and southerly flow at the surface. A cold front located to our north will be on its way southward while a dryline located over northern Mexico and West TX will also be advancing eastward throughout the day. Both of these features should be the next focus for our next round of convection and heavy rainfall potential. This would likely commence late Tuesday afternoon and continue through the evening, more on that below. && .LONG TERM... (Tuesday night through Sunday) Issued at 124 AM CDT Mon May 18 2026 A big pattern change is forecasted for the long term as we remain under southwest flow aloft which usually allows for disturbances to impact our area and take advantage of the rich moisture and unstable air in place. As such, it seems likely that multiple disturbances could impact our area as a dryline will be situated just off to our west across west TX and will have advanced eastward through the day Tuesday before beginning its daily retreat back westward. Similarly, the previous mentioned cold front will be advancing southward and as it does so numerous Hi-res models and ensembles suggest that convection would blossom along and ahead of this front by Tuesday evening. Most models highlight areas to our north across central TX where discrete supercells would initially be possible before quickly congealing into a line and working its way southeastward towards our area. What's interesting to note is just how consistent all of these models continue to be at targeting this scenario. As this convection moves closer we could see a secondary line of storms form out west from the aforementioned dryline convection if it forms over northern Mexico. Depending on how robust this activity becomes will determine how far eastward it advances. SPC currently has most of the area in a level 1 or 2 of 5 risk for severe weather for this time period. With the continued moisture remaining across the area any convection that does form will be capable of very heavy rainfall. Eventually this front becomes stationary towards the middle of the week and washes out somewhere across our area. This now stationary front will be the continued focus for additional shower and thunderstorm activity throughout the period as we remain entrenched in a very moist airmass with continued southwest flow aloft. The main forecast challenge in the coming days will be identifying which features will provide the strongest focus for storms each day. The pattern transitions from a dryline/shortwave-driven severe weather pattern late Tuesday to a frontal and eventually a surface boundary-driven heavy rain and storm regime later in the week. Global models continue to hint at this pattern continuing into and even beyond next weekend as disturbances aloft continue to ride over our area and ignite the potential for additional rounds of showers and thunderstorms. While most of the rain will be beneficial for many areas, there are some beginning signs that we could see heavier rounds that may lead to localized flooding concerns. However due to the difficult timing and placement of these additional rounds and the numerous surface and outflow boundaries from previous convection it's still too hard to decipher which areas may see heavier amounts and when. Bottom line is an active and wet pattern looks likely for the entire area starting early next week. Continue to check back as details continue to get clearer over the coming days. && .AVIATION... (12Z TAFS) Issued at 547 AM CDT Mon May 18 2026 All terminals have MVFR ceilings this morning and will remain MVFR until around noon. Ceilings will lift to VFR. Wind speeds will increase and become gusty this afternoon. MVFR ceilings will return around midnight tonight. There is a less than 20% chance for showers or thunderstorms during the evening in Austin and San Antonio. If convection does form, it could lower ceilings or visibility to MVFR for a short time. && .PRELIMINARY POINT TEMPS/POPS... Austin Camp Mabry 92 78 91 72 / 10 20 50 70 Austin Bergstrom Intl Airport 92 79 91 73 / 10 20 50 70 New Braunfels Muni Airport 92 78 91 72 / 10 20 40 60 Burnet Muni Airport 88 75 87 70 / 10 10 50 70 Del Rio Intl Airport 98 78 95 72 / 10 10 30 50 Georgetown Muni Airport 91 77 90 71 / 10 20 60 70 Hondo Muni Airport 92 78 91 72 / 10 20 40 60 San Marcos Muni Airport 92 78 92 73 / 10 20 40 70 La Grange - Fayette Regional 91 79 91 73 / 10 20 40 60 San Antonio Intl Airport 92 78 91 73 / 10 20 40 60 Stinson Muni Airport 93 79 92 73 / 10 20 30 60 && .EWX WATCHES/WARNINGS/ADVISORIES... None. && $$ SHORT TERM...CJM LONG TERM....CJM AVIATION...05  318 FXUS65 KRIW 181050 AFDRIW Area Forecast Discussion National Weather Service Riverton WY 450 AM MDT Mon May 18 2026 .KEY MESSAGES... - Snow will continue to fall across the Wind River Basin, Natrona County and Sweetwater County this morning. Greatest travel impacts expected around Lander, Casper, South Pass, and over Interstate 80. Gusty winds and snow will bring reduced visibilities and possibly icy surfaces with colder temperatures moving in. Wind gusts up to 70 mph will be possible over South Pass and over Interstate 80. - Warming trend and mainly dry conditions for most of the CWA Tuesday and Wednesday with another Canadian cold front impacting the area on Thursday. This storm does not look to be as cold as the current storm. - Medium confidence for above normal temperatures returning for at least the first 2/3 of the holiday weekend. && .DISCUSSION... Issued at 240 AM MDT Mon May 18 2026 Rain changed over to snow in the Wind River Basin and across Sweetwater County just a few hours ago after 11pm Sunday night. Much of Natrona County is around 37F degrees as of 08Z (2am), with precipitation still falling as rain. The forecast remains on track this morning, with the threat of snow and wind impacting areas from South Pass southward into Sweetwater County. The 700mb low from this storm system will be passing close to the CO/WY border this morning, resulting in a tight temperature and pressure gradient. 700mb northeast winds of 50-60kt will occur from the Green Mountains/Rattlesnake Range into Sweetwater County. This will result in wind gusts of 60 to 70 mph occurring this morning over locations like South Pass down to the Rock Springs/Green River area. Windy conditions (wind gusts up to 35 mph) will be widespread across the CWA this morning as the storm system moves over CO this morning. Snowfall amounts of 2 to 6 inches is still expected across portions of Natrona County, the Lander Foothills and the eastern half of Sweetwater County. Travel conditions could be difficult this morning due to the blowing snow and icy roads. Impacts from snow accumulations on roads is likely to only last through 15Z/16Z (9am or 10am) as it will be more difficult for the snow to stick due to the high sun angle. These impacts will begin to decrease through the morning, with areas like Lander and Casper improving first as snow begins to end toward midday. Impacts along I-80 will last the longest due to the proximity of the 700mb low, but is expected to wane between 18Z and 21Z as snowfall ends. Winds will be decreasing across the area after 18Z as well, with the stronger winds of 35 to 40 mph continuing from South Pass southward into Sweetwater County and decreasing through the afternoon. Needless to say, temperatures will be anywhere from 5 to 25 degrees colder today and about 15 to 30 degrees below normal. Winds will continue to decrease this evening, as the storm system quickly exits over the Central Plains and light winds (10kt or less) expected for most areas by 06Z Tuesday. Fog development could occur as late as sunrise Tuesday morning as clouds are expected to remain in place across central and southern portions of the CWA through much of the night tonight. Dry and warming conditions are expected Tuesday and Wednesday, with another Canadian storm system impacting the area on Thursday. This system doesn't look to be as cold as today's storm and snow levels staying around 7000ft at this time. Model guidance remain split at this time, but confidence is medium for a mainly dry holiday weekend for at least 2 of the 3 days. && .AVIATION /12Z TAFS THROUGH 12Z TUESDAY/... Issued at 445 AM MDT Mon May 18 2026 Impactful winter weather conditions will continue for most terminals this morning. IFR/LIFR conditions are expectedto continue through 18Z at KCPR, KRKS and KLND. KCOD looks to remain north of the precipitation, but showers will impact the nearby terrain. KCPR and KLND are worth mentioning specifically for snowfall, as these locations will see snow for much of the day due to favorable upslope flow. Elsewhere, snow should generally taper off during the afternoon hours Monday. Mountain obscurations will be in place for all locations except the far western mountains through the day today, with gradually improving conditions after 00Z as clouds begin to scatter out. Expect gusty north to northeast winds today, gusting in to the 20 to 30kt range for most locations through 18Z. KRKS will be windiest given its position close to the storm center, so gusts will be higher in the 40 to 50kt range, gradually decreasing through the afternoon. KRKS also has a chance (20%) of morning fog on Tuesday. KRIW, KLND and KCPR also have a 20-30% chance for fog Tuesday morning, but will be dependent on how quickly the clouds clear out after 06Z Tuesday. Please see the Aviation Weather Center and/or CWSU ZDV and ZLC for the latest information on icing and turbulence forecasts. && .RIW WATCHES/WARNINGS/ADVISORIES... Winter Weather Advisory until 6 PM MDT this evening for WYZ002- 003-005-007>011-014-016-017-026>029. Winter Storm Warning until 6 PM MDT this evening for WYZ015- 018>020-022-030. && $$ DISCUSSION...LaVoie AVIATION...VandenBoogart  378 FXUS62 KMHX 181052 AFDMHX Area Forecast Discussion National Weather Service Newport/Morehead City NC 652 AM EDT Mon May 18 2026 .WHAT HAS CHANGED... Updated aviation discussion for 18/12Z TAFs. && .KEY MESSAGES... 1) Above normal to near-record high temperatures and rain-free conditions to continue through mid-week. 2) A frontal system approaches the area late week, bringing the next appreciable chance of showers and thunderstorms && .DISCUSSION... KEY MESSAGE 1...Notably warm low-level thicknesses beneath anomalous mid-upper level ridging will continue to support above to well above normal temperatures across the Carolinas through the middle of the week. While well above normal temperatures are expected, temperatures look to stay just shy of records. It may be close across the coastal plain, though. Additionally, despite increasing low-level moisture, ridging aloft should tend to suppress convective activity outside of perhaps a rogue shower or thunderstorm where convergence is maximized along the seabreeze (Albemarle Sound/NRN OBX vicinity). Still, probs of this occuring are low enough to keep out of the forecast with this update. KEY MESSAGE 2...The mid-upper level ridge is forecast to break down some late-week and into the weekend. This should allow a front to drop south into the Thursday into Friday. There continues to be some uncertainty regarding whether or not the front fully makes it through ENC, whether it stalls, or whether it lifts quickly back north as a warm front. Given the strength of the ridge, it stands to reason that the front will struggle to get fully through ENC, and the forecast reflects this scenario. Then, ridging may try to make a comeback late in the weekend, which would favor the front lifting back north as a warm front by early next week. Based on the above, increasing moisture and instability along the frontal zone should support an increased risk of showers and thunderstorms. Probabilistic guidance shows a solid chance of 0.25"- 0.75" each day from Thursday into the weekend. However, it should be noted that those amounts will be highly dependent on the evolution of the frontal zone. Initially when the front drops into the area, there may be just enough flow aloft to support some thunderstorm organization and perhaps a marginal risk of strong to severe thunderstorms. Machine learning and analog guidance support this potential as well. However, no one day stands out as having a higher risk of severe thunderstorms. Notably high PWATs along the frontal zone should support higher rainfall rates in convection. However, notable hydro impacts are not expected due to the recent dry stretch and ongoing drought conditions. && .AVIATION /09Z MONDAY THROUGH FRIDAY/... IFR VIS/CIG for SW portions of eastern NC become VFR this morning, expected to remain VFR through the day. Sub-VFR chances return tonight into Tuesday morning with another round of fog/low stratus. Generally clear skies today, with a shift in winds from SW to S associated with the daily seabreeze, gusting to 15-20 knots behind it. Tonight, chances for decoupling are higher, and solid low level moisture primes us for another fog/low stratus night. Like this morning, expect things to initiate along SW portions of the CWA, before slowly progressing north and east. As a reasonable worst case scenario IFR/LIFR VIS and CIG are possible. Highest chances for OAJ, decreasing as you go north. Outlook: A dry seabreeze pattern looks to continue through Wednesday. Beyond then, a frontal boundary sagging south into ENC is expected to bring an increasing risk of SHRA, TSRA, and sub-VFR conditions. && .MARINE... A summer-like pattern continues through the middle of the week, with a daily building of winds to 10-20kt each afternoon and evening as the thermal gradient tightens. This will especially be the case for the inland rivers and sounds and the nearby coastal waters within 20nm of the coast. This should also support periods of 3-5ft seas. Outlook: A frontal boundary is forecast to sag south into the area late-week, then meander around the area through the upcoming weekend. This leads to lower confidence regarding winds and seas, but especially wind direction. In general, the risk of 25kt+ winds appears low during this time ahead of the front, with slightly higher chances of seeing 25+kt gusts behind the front. There will be an increased risk of thunderstorms along the front. && .MHX WATCHES/WARNINGS/ADVISORIES... NC...None. MARINE...None. && $$ DISCUSSION...RJ AVIATION...RJ MARINE...RJ  369 FXUS65 KCYS 181052 AFDCYS Area Forecast Discussion National Weather Service Cheyenne WY 452 AM MDT Mon May 18 2026 .UPDATE... Issued at 449 AM MDT Mon May 18 2026 Monitoring blizzard conditions over the northern Snowy Range Foothills at this hour. Current observations along the Interstate 80 corridor from Walcott Junction to Arlington show visibility as low as 1/8th of a mile with winds gusting 50 to 65 MPH. Going to give this another hour or so, and then may need to upgrade to a Blizzard Warning if this continues. Also monitoring central Carbon County with similar conditions just starting in and around Rawlins. && .KEY MESSAGES... - Accumulating snow through Monday afternoon with Winter Storm Warnings for many of our high elevation and mountain zones and Winter Weather Advisories for nearby zones. - Near record cold Monday and Monday night will lead to widespread freezing temperatures, which may damage sensitive vegetation and outdoor irrigation systems. - Slow warming trend by the mid to late week with temperatures near normal by Thursday and Friday. Chance of showers and a slight chance of thunderstorms each day through Friday evening. && .SHORT TERM /THROUGH TUESDAY/... Issued at 255 AM MDT Mon May 18 2026 Late season winter storm ongoing across southeast Wyoming with everywhere above 6500 feet changing to snow within the last 3 hours. Rain/snow line is roughly 10 miles west of Cheyenne at this hour based on area webcams which show snowfall at the Warren Exchange along I-80. Most of Interstate 80 west of there shows very difficult travel conditions with some of the worst conditions on the I-80 Summit, which is currently experiencing visibility below one half mile in heavy snow. Snow is starting to accumulate on the roads above 7000 feet and expect this to continue through much Monday morning. Storm system is just starting to intensify at this hour...as seen by the current IR Satellite loop with cooling cloud tops over most of Wyoming and the distinct "comma cloud" beginning to take shape. No changes yet to Winter Weather headlines, but will need to keep a close eye on the I-25 corridor, the Pine Ridge, and the higher hills around Scottsbluff and Banner county for potential extensions this morning. Thankfully, even if snowfall rates become an issue, snow will struggle to stick on the pavement shortly after sunrise. Snow will be ongoing as we head into this afternoon, although with the high May sun angle impacts should be limited with melting on area roadways. Snowfall rates will begin to ease down during the middle of the afternoon as the best dynamic forcing shifts east into the high plains. Some rain/snow mix expected down to 4500 to 5000 feet, but little in the way of accumulations since this will occur during the daytime hours. Remnant snow (or rain/snow mix below 5000 feet) will taper off and finally end by midnight tonight as the storm system transitions to an open wave trough and rapidly ejects northeast. Once all is said and done, this system should provide much needed moisture to the area with around a half inch of precip for the eastern plains, and close to 1.00 inch to as high as 1.50 inches for southeast Wyoming. Main forecast concern after today will be how quickly we clear out at night. There is increasing confidence that a good part of the eastern plains with clear out by daybreak Tuesday with portions of Carbon county below 50% cloud cover as well. A hard freeze is expected late tonight through most of Tuesday morning, with freezing temperatures likely lasting until shortly before noon in portions of the forecast area. This is due to a record breaking unseasonably cold airmass behind the main storm system, which is forecast to settle over the area today. Current 10th to 25th percentile low temperatures tonight are between 14 to 20 degrees over most of the high valleys in southeast Wyoming, with 17 to 27 degrees across the eastern plains. Upgraded the Freeze Watch to a Freeze Warning for east central Wyoming and far northwestern Nebraska since these are the most likely zones to see clearing skies earlier in the night. Kept the Watch going for the remainder of the area, but mainly to see how this current storm system and potential snowfall pans out first. Conditions will improve a little on Tuesday with 700mb temperatures between -2c to -5c under northwest flow. High temperatures will be warmest where there is no snow pack...mainly over far eastern Wyoming and western Nebraska with highs in the 50s to low 60s. Further west, expect highs to generally be in the 40s and even upper 30s in areas with the deepest snow pack. && .LONG TERM /TUESDAY NIGHT THROUGH SUNDAY/... Issued at 230 PM MDT Sun May 17 2026 Certainly less active than the short term, but the long term period will still have some impacts. We will likely dip below freezing again on Tuesday night especially in regions that don't melt away all of their snow (i.e. areas west of the I-25 corridor). On Wednesday, temperatures will gradually moderate into the upper 50s to near 60 east of the Laramie Range and upper 40s to lower 50s west given weak isentropic ascent/warm advection as the longwave trough responsible for our anomalously cool weather dampens. There may be enough lingering moisture for a few showers and thunderstorms primarily over the higher terrain, however probabilities of seeing QPF > 0.05" are running at about 25%, so any moisture is unlikely to be beneficial. Given dry boundary layers as shown on model forecast soundings show a very dry boundary layer with surface dewpoint depressions exceeding 40 degrees, showers and thunderstorms will likely produce far more wind than rain. Temperatures gradually warm on Thursday and Friday as a series of shortwave troughs embedded in quasi-zonal flow traverse across Eastern Wyoming and Western Nebraska, leaving in low (30%) chances for high-based showers and thunderstorms. Highs will gradually increase to climatological values (mid-upper 60s for Cheyenne to near 70 for the Nebraska Panhandle). Heading into the weekend, we will begin to dry out and encounter a faster warming trend to above- average temperatures as weak mid-level ridging establishes itself over the Rocky Mountain West, with no widespread or beneficial precipitation chances in sight. && .AVIATION /06Z TAFS THROUGH 06Z TUESDAY/... Issued at 1153 PM MDT Sun May 17 2026 Aviation trends over the next 12 hours will consist of deteriorating conditions as a winter system pushes into the area. Rain will transition to snow at southeast Wyoming terminals, causing visibility reductions and low CIGs. Windy conditions around KRWL could also lead to areas of blowing snow, further reducing visibility. Western Nebraska terminals will primarily see rain, however low CIGs will likely develop during the morning hours. Snow will continue through the day at southeast Wyoming terminals, so IFR conditions are expected through much of the TAF period. MVFR conditions are more likely at Nebraska terminals for the first part of the day, with CIGs continuing to lower through the afternoon to IFR criteria. && .CYS WATCHES/WARNINGS/ADVISORIES... WY...Freeze Watch from late tonight through Tuesday morning for WYZ106-113-115>119. Freeze Warning from 8 PM this evening to 10 AM MDT Tuesday for WYZ101-102-107-108. Winter Weather Advisory until 6 PM MDT this evening for WYZ101- 105-106-111-115-117. Freeze Warning until 10 AM MDT this morning for WYZ102. Winter Storm Warning until 6 PM MDT this evening for WYZ103- 104-109-110-112-114-116. Freeze Watch from this evening through Tuesday morning for WYZ104-105-109>111. NE...Freeze Watch from late tonight through Tuesday morning for NEZ002-003-020-021-054-055. Freeze Warning from 8 PM this evening to 10 AM MDT Tuesday for NEZ019-095-096. && $$ UPDATE...TJT SHORT TERM...TJT LONG TERM...NB AVIATION...SF  532 FXUS62 KMFL 181057 AFDMFL Area Forecast Discussion National Weather Service Miami FL 657 AM EDT Mon May 18 2026 ...New AVIATION... .KEY MESSAGES... Updated at 656 AM EDT Mon May 18 2026 - High risk of rip currents along the east coast of South Florida will continue through at least Tuesday evening as breezy easterly winds prevail. - Scattered showers and thunderstorms will develop mainly across SW Florida again today. Low-end chance for an isolated severe thunderstorm. Rain chances will remain elevated over the next several days. && .SHORT TERM... (Today through Tuesday) Issued at 119 AM EDT Mon May 18 2026 South Florida is going to be sandwiched between an upper level low centered near the Bahamas and a ridge of high pressure over the deep south and Gulf. The low over the Bahamas will usher in some positive vorticity pulses from the northeast and increase instability across the area. The easterly flow has a chance to become more dominant than yesterday, meaning that the Gulf breeze may not be able to move inland at all. However, much of the guidance does have it forming and getting stuck just barely on land. If this boundary does move more inland it will get pinned no further than along the metro areas of Collier county and Naples. SBCAPE is forecast to be 2000-3000 J/kg with steep low level lapse rates of 8-9 C/km and 500mb temps near -10 deg C. The dry air column has mostly been eroded, although some level of dry air still remains in the mid-levels along with an inverted-V profile on model soundings. This suggests that a couple of storms could become marginally severe again via wind gusts. Additionally, with these steep low level lapse rates and increased CAPE, updraft health has a good chance to be sustained even with the inhibition of the upper level ridge. Given the upper level ridge presence, the risk for strong to severe storms is highly conditional again today, but with the parameters explained above, support is there for an isolated severe thunderstorm or two occurring along the Gulf breeze where the strongest lift and near-surface convergence occurs. Both severe winds and quarter-size hail will be possible today. On Tuesday, the weather pattern remains largely the same although its more uncertain to determine severe potential. The easterly flow will remain in place and result in another day with a Gulf breeze that gets trapped from advancement, but 500mb temps will rise a couple of degrees to -8 deg C and some extra dry will filter in the mid-levels, which will lower instability. Nevertheless, typical wet season scattered showers and storms are still expected on Tuesday with most of the activity occurring in Southwest Florida with the ongoing easterly flow regime. High temperatures for today and Tuesday will again range from the mid to upper 80s in Southeast Florida to the low to mid 90s for Southwest Florida. && .LONG TERM... (Tuesday night through Sunday) Issued at 1257 AM EDT Mon May 18 2026 Longwave ridging will be the dominant pattern aloft for the eastern CONUS during the middle portion of the week. Florida will find itself in between an H5 centroid to its west over the southern Gulf and an H5 centroid to its east near Bermuda. Within the overall ridging pattern, ensemble guidance is in pretty good agreement of showing a cut off low meandering around the northern Caribbean just east of the Bahamas. This area of low pressure will provide increased forcing for storms over the Atlantic waters as several lobes of vorticity advect westward near the vicinity of the Florida coastline. Florida will remain under rich moisture through the period, but some deeper pockets look to raise PWATs to near 1.8 inches, which is within the 75th percentile for this timeof year. At the surface, winds will remain mostly easterly, but wind speeds will be slightly weaker than in the beginning of the week as pressure gradients relax across the eastern seaboard. As a result of this predominant easterly flow, the Gulf breeze won't be able to advance as far east. This will result in most afternoon thunderstorm activity favoring interior and portions of southwest Florida each day. Overall, PoPs will generally be in the 30% to 40% range across the peninsula each day, with higher 55% to 65% PoPs along the sea breeze convergence zones. Main threats will be frequent lightning, locally heavy downpours, and gusty winds. Despite the cutoff low nearby, 500 mb heights will actually be between 586 to 589 dm across South Florida, which is near to slightly above average for this time of year. This will in turn lead to slightly above normal temperatures area wide, with high temperatures in the upper 80s and low 90s. With moisture staying steady throughout the week, heat indices will remain in the upper 90s and lower 100s through the period as well. Zooming into the forecast a little bit, diurnal heating will drive most of these high temperatures each afternoon. But, with increased chances of showers moving onshore from the Gulfstream during the morning (particularly for the middle part of the week), cloud cover and rain may keep things cooler over certain spots during the day. Conversely, increased cloud cover and rain during the nighttime hours may suppress radiational cooling and keep things slightly warmer overnight. For the most part, widespread Moderate HeatRisk (level 2 of 4) is expected each day. However, long range ensembles are indicating that pressure heights will increase slightly as longwave ridging shifts east and the cut off low dissolves. This will result in warmer temperatures for the weekend, with the NWS Prototype Probabilistic HeatRisk tool showing a 40 to 50 percent chance of Major heat impacts for the east coast metro areas. && .AVIATION... (12Z TAFS) Issued at 656 AM EDT Mon May 18 2026 Breezy easterly winds will continue with SHRA coverage forecast to increase along the east coast of South Florida over the next few hours before activity pushes inland by 17-19z. Wind gusts will rise up to 20-25 kts as well. At KAPF, SHRA/TS coverage will occur after 18-19Z. && .MARINE... Issued at 119 AM EDT Mon May 18 2026 A moderate to fresh easterly breeze will remain established across the local waters early this week. Scattered showers and storms will be possible each day with extra activity expected for the Gulf waters compared to the Atlantic waters. Periods of rough seas and gustier winds are expected in and around thunderstorm activity. Atlantic seas early this week are expected generally at 3-4 feet with Gulf seas of 2 feet or less. && .BEACHES... Issued at 119 AM EDT Mon May 18 2026 A high risk for rip currents continues for all of the Atlantic beaches early this week as breezy onshore winds persist. && .PRELIMINARY POINT TEMPS/POPS... Miami 87 78 87 77 / 30 30 40 20 West Kendall 88 75 89 74 / 40 30 50 10 Opa-Locka 88 77 88 77 / 30 30 40 20 Homestead 87 77 88 77 / 30 40 40 20 Fort Lauderdale 86 78 86 78 / 30 40 40 30 N Ft Lauderdale 85 77 85 77 / 30 40 30 20 Pembroke Pines 89 78 90 78 / 30 30 30 20 West Palm Beach 86 77 86 77 / 30 40 30 10 Boca Raton 86 78 86 78 / 20 40 30 20 Naples 92 74 92 74 / 70 20 90 10 && .MFL WATCHES/WARNINGS/ADVISORIES... FL...High Rip Current Risk through Tuesday evening for FLZ168-172-173. AM...None. GM...None. && $$ SHORT TERM...Redman LONG TERM....NMP AVIATION...Rizzuto