396 FXUS61 KBTV 180701 AFDBTV Area Forecast Discussion National Weather Service Burlington VT 301 AM EDT Mon May 18 2026 .WHAT HAS CHANGED... As of 300 AM EDT Monday... No major changes have been made to the forecast. Above normal temperatures are expected across the region today, with increased chances for thunderstorms on Tuesday. && .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 main cold 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  499 FXUS61 KCTP 180702 AFDCTP Area Forecast Discussion National Weather Service State College PA 302 AM EDT Mon May 18 2026 .WHAT HAS CHANGED... * Continue to trend afternoon highs below NBM guidance due to known warm bias * Changed wording for showers/storms Monday from probability (Slight Chance) to coverage (Isolated). && .KEY MESSAGES... 1) Hottest temperatures of the year so far forecast the next couple of days 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 the next couple of days with highs pushing into the 80s and 90s. Daytime high temperatures will be steadily rising today through early week. An anomalous upper ridge amplifying over the east- central U.S. will help to create very warm to hot, summerlike conditions centered on Monday and Tuesday. 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. High temperatures will peak in the mid 80s to lower 90s Monday and Tuesday and could challenge daily records in some locations. See the Climate section for more details. Manual adjustments were made to lower NBM maxT by a few degrees 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 quite 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 some stray afternoon and early evening showers or thunderstorms Monday and Tuesday. Most folks should stay dry, but thunderstorms could drop a quick 0.10 to 0.25" of rain in any one location. New... Rather strong cap noted on the 00Z Monday observed sounding over ILN Ohio, so might be hard to see much activity on Monday. Activity late this afternoon was isolated near the MD border, then a few showers formed just east of State College early this evening, most likely due to a weak lee-side trough. ------------------------------------------------------------- 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 Dayweekend. 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 /06Z MONDAY THROUGH FRIDAY/... Patchy fog remains a low (<30%), but nonzero, possibility tonight with light winds and mainly clear skies. Localized visibility drops have been observed (e.g. KMUI in Lebanon County briefly dropping to 2.75 miles at 00:35Z Monday), though model guidance has trended toward less numerous mist/fog across the region. For this reason, we've maintained no mentions of visibility restrictions to our TAF sites. Otherwise, regionwide VFR is expected through Monday afternoon. Regarding the chance for convection Monday afternoon: 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 92 in 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...Banghoff/Martin KEY MESSAGES...Lambert/Banghoff/Martin DISCUSSION...Lambert/Banghoff/Martin AVIATION...Teare/Lambrech CLIMATE...Dangelo/Steinbugl  715 FXUS63 KDTX 180707 AFDDTX Area Forecast Discussion National Weather Service Detroit/Pontiac MI 307 AM EDT Mon May 18 2026 .KEY MESSAGES... - Warm and humid conditions will exist today and Tuesday. This brings the risk for severe weather each day, mainly during the afternoon and evening hours. Thunderstorms will be capable of producing damaging winds, large hail and isolated tornadoes. - Cooler and drier conditions expected Wednesday and Thursday. && .DISCUSSION... Warm frontal boundary responsible for the prolific hail producing supercellular activity across portions of the Saginaw valley and northern thumb late Sunday will finally ease north of the region this morning as higher magnitude warmth increases influence within deepening southerly flow. Benign conditions ensured thru late morning as stability holds under modest capping. Influx of higher quality moisture will commence during this time, establishing a notable moisture gradient from west to east by early afternoon /dewpoint of mid 60s west to upper 50s east/. This affords a moderate level of diurnal boundary layer destabilization for at least western sections. Given an afternoon temperature of middle 80s, mlcape projection of upwards of 1500-2000 j/kg will peak across the Saginaw valley and down through the Highway 23 corridor. This leaves a receptive downstream environment for potential reorganization/ expansion of any MCV governed remnant nocturnal convective activity spilling downstream. A fairly strong model consensus exists on this scenario, targeting lower Michigan for a mid-late afternoon increase in coverage. A broader threat window locally between 19z and 01z with dependence on pace of the MCV. The background wind field remains modest, but subject to a localized meaningful increase both across the lower levels and with greater depth as the feature moves through. Supportive environment to offer a risk of both large hail and damaging wind gusts, with greater overall potential with westward extent. A focused area of higher SRH does materialize as low level flow backs briefly with a slight shift in the pressure gradient orientation. Therefore, cannot completely discount the possibility for a more organized, rotating updraft to present a brief, isolated tornado threat. Outside of the convective window, forecast continues to highlight gusty southerly conditions reaching 30 to 35 mph at times today. The seasonably warm and humid conditions will exist again Tuesday ahead of a cold front. A more muddled early day picture in terms of both cloud cover and precipitation chances, as a portion of the model solution space suggest possible activity prior to 18z owing to some combination of the ongoing moisture advection and remnant midwest convection leftover from tonight. Degree and pace of destabilization certainly still subject to change. Assumption for at least a weakly unstable environment timed favorably with an evening cold frontal passage will present an opportunity for deeper updrafts to organize within a sufficient background deep layer wind field along the frontal zone. The SPC Day 2 outlook maintains a slight risk designation to highlight the associated strong wind and large hail threat for the late Tuesday period. Warm sector environment will again become diurnally gusty, with winds reaching 30 to 35 mph from the south at times. Notably cooler post-frontal environment arrives Wednesday. This will occur with the backdrop of increasing low to mid level ridging, ensuring a stretch of dry and stable conditions lasting into Thursday. Low level thermal trough marked by 850 mb temperatures of lower single digits, lending to below average readings during this time. Coldest conditions Thursday morning as the surface high centers locally - lows dipping into the 30s in some locations. Dry conditions likely to hold under a modest warming trend Friday, as the next system organizes upstream. This system will introduce the next chance of rain Friday night into Saturday. && .MARINE... A warm front releases north across Lake Huron this morning, with southerly winds expanding across all local waters. Strong low level jet winds will struggle to mix down over the open waters where cool water temperatures maintain stable over-lake conditions. Gusty southwest flow will thus be confined to the nearshore waters, aided by warmer water temperatures and land influence. Frequent gusts today and Tuesday are expected to hold between 25 and 30 knots, but an isolated gust to 35 knots over Saginaw Bay cannot be entirely ruled out. Small Craft Advisories are in effect for today and will be needed Tuesday as well. More localized wind/wave impacts arrive with thunderstorm activity this afternoon-evening, and again Tuesday when a cold front sweeps through the area. There is potential for some of these storms to be strong to severe with all modes of severe weather in play. The cold front comes through Tuesday night, followed by high pressure filling in mid-week to support a quieter and more seasonable late May pattern. && .PREV DISCUSSION... Issued at 1145 PM EDT Sun May 17 2026 AVIATION... VFR conditions persist for the remainder of the night with only scattered pockets of mid/high cloud. Breezy southwesterly winds develop by late morning with peak gusts between 25-30kts. A broken line of remnant upper Midwest convection is set to arrive over SE MI by afternoon, roughly 19-00Z, offering the next thunderstorm chances. Given some lingering uncertainty in exact coverage of storms, have maintained Prob30 mention. D21/DTW Convection... No convection forecast this evening through early Monday afternoon. A broken line of showers and storms are then possible between 20-00Z. DTW THRESHOLD PROBABILITIES... * Low for thunderstorms this afternoon. * Low for ceilings aob 5000ft today. && .DTX WATCHES/WARNINGS/ADVISORIES... MI...None. Lake Huron...Small Craft Advisory from 10 AM this morning to 10 PM EDT this evening for LHZ421-422-441>443. Lake St Clair...Small Craft Advisory from 10 AM this morning to 10 PM EDT this evening for LCZ460. Michigan waters of Lake Erie...None. && $$ DISCUSSION...MR MARINE.......MR AVIATION.....KDK You can obtain your latest National Weather Service forecasts online at www.weather.gov/detroit.  722 FXUS63 KLBF 180707 AFDLBF Area Forecast Discussion National Weather Service North Platte NE 207 AM CDT Mon May 18 2026 .KEY MESSAGES... - A cool, raw day is in store for western Nebraska Monday as daytime highs remain 20-30F below normal and light rain crosses the area. - Cooler overnight lows Monday and Tuesday night may lead to the potential for at least patchy frost/freeze conditions west of Highway 83. - Periodic light precipitation potential will persist through the upcoming week as daytime highs climb to seasonable and then above normal values by the late weekend. && .SHORT TERM /THROUGH TUESDAY NIGHT/... Issued at 206 AM CDT Mon May 18 2026 Early this morning, scattered showers were lifting north and east across the Sandhills and portions of the Nebraska Panhandle. This was associated with a weak impulse located around h7 ejecting ahead of the parent trough situated across the Great Basin. Light rain is possible beneath this activity as low level humidity remains fairly high within a post frontal airmass. Temperatures largely sit in the upper 40s to lower 50s with breezy north winds. Cloud cover should keep temperatures from falling too significantly though morning lows will still reach 5-10F below normal for late May. Monday/Monday Night...northerly low-level flow will persist through the daytime across western Nebraska. The frontal inversion will support cloudy to mostly cloudy conditions for the bulk of the daytime and combined with persistent cold air advection, should keep temperatures in check across the region. Afternoon highs will likely only reach the lower 40s in the northwest to near 50F in our far south and east. These values will approach 30F below normal for mid- May and when factoring in steady north winds gusting 20 to 30 mph, feels like temperatures will struggle to climb out of the lower 30s for portions of the area. Main upper trough will begin to pivot by midday as it crosses the central Rockies to the west. This will lead to a fairly expansive area of thunderstorms along a stalled frontal boundary and associated baroclinic zone draped in southeast Nebraska. It is here where the Storm Prediction Center has maintained a Moderate Risk (Level 4 of 5) extending south into Kansas and folks with interests in these locations should check for local information regarding this threat from reliable sources. Further west in the local area, the cooler temperatures will all be prevent the threat for severe weather. While MUCAPE may approach 500 j/kg, perhaps enough for a rumble of thunder across central Nebraska, severe weather is not anticipated west or north of the Tri- Cities. Lift via increasing height falls, cyclonic vorticity advection, and frontal forcing should lead to expanding precipitation primarily for the Panhandle into portions of north central Nebraska. PoPs should gradually increase this afternoon with the highest probabilities arriving by early evening. Even with the cooler temperatures, precipitation is expected to fall as rain with colder air waiting to filter in until precipitation has departed. Rates should be slow and steady given primarily synoptic lift and limited if any instability. The result is showery activity overtop the widespread stratus. HREF probability matched mean (PMM) output suggests most locations see < 0.10" outside the Panhandle and our far northern counties. The going forecast matches this well with most locations seeing < 0.05" save for the Pine Ridge vicinity where closer to 0.20" seems plausible. Precipitation exits the area shortly after Midnight tonight with temperatures then falling to the upper 20s in the west to middle 30s east. The going forecast lows of 32F and 33F at North Platte and Valentine respectively fall into the lowest 10% of observed values for the May 19 date. Will defer to later forecasts for potential Frost/Freeze headlines but believe these will be necessary given recent updates of susceptible vegetation. Tuesday/Tuesday Night...behind departing trough, mid-level heights will begin to build quickly across the region. Surface high pressure will nose in from the west and support steady northwesterly winds. Increasing h85 temperatures and downsloping flow should produce a warmer day as temperatures look to return to the upper 50s to lower 60s. Subsidence aloft will allow for eroding clouds and dry conditions. High pressure will settle to the east and return southerly flow should become established by late evening. Cloud cover should increase as a result with subtle moisture advection over the High Plains. Forecast lows remain on par with Monday night's forecast values so additional Frost headlines may need to be considered if the current forecast holds. && .LONG TERM /WEDNESDAY THROUGH SUNDAY/... Issued at 206 AM CDT Mon May 18 2026 The extended pattern will generally favor warming temperatures with periodic rain and thunderstorm potential. Southwesterly flow should return by mid week as modest troughing forms west of the Continental Divide. Moisture should increase across the area and set the stage for low-end PoPs periodically. Temperatures should moderate steadily with NBM median MaxT and MinT values showing 4-6F day-over-day climbs. Given the expected daytime temperatures returning to seasonable and then abnormally warm values, believe any precipitation potential will likely come in the form of thunderstorms. Generally weak mid-level flow will likely limit the threat for any widespread severe weather event at this time. An approaching trough on Friday may pose the greatest potential for western Nebraska as a cool front moves out of the Northern Plains. NBM matches this timeframe with 10-20% potential for seeing > 0.25" precipitation but greater probabilities are apparent east of the local area. Beyond Friday, drier conditions appear likely as precipitable water values fall off and upper-level ridging builds across the Western CONUS. NBM probabilities for exceeding 90F climbs by late weekend, with probabilities reaching 20-40% by Sunday and 40- 70% by Monday. Higher percentile outputs suggest mid to upper 90s for these days, but inner-quartile spreads remain reasonably large so certainty is low at this time. && .AVIATION /06Z TAFS THROUGH 06Z TUESDAY/... Issued at 1224 AM CDT Mon May 18 2026 Increasing clouds will bring extensive degraded aviation conditions for western Nebraska terminals. Early morning satellite shows low clouds expanding across South Dakota to the north and Kansas to the south. This is behind a cold front that passed through the area earlier today. Expect low stratus to eventually fill in over western Nebraska with prolonged MVFR conditions likely. Northern Nebraska, including the VTN terminal, could potentially see IFR/LIFR conditions briefly by late morning. This is hinted at by the usually reliable HRRR output with GFSLAMP suggesting a longer duration period of IFR conditions through the daytime. Will keep the LIFR conditions brief and highlight the longer IFR duration with adjustments likely in later forecasts. Winds should remain fairly steady out of the north with gusts ranging from 20 to 30 knots across the region. && .LBF WATCHES/WARNINGS/ADVISORIES... None. && $$ SHORT TERM...NMJ LONG TERM...NMJ AVIATION...NMJ  693 FXUS65 KPUB 180706 AFDPUB Area Forecast Discussion National Weather Service Pueblo CO 106 AM MDT Mon May 18 2026 .KEY MESSAGES... - Extreme fire danger is expected across our southern plains today, with southwest winds gusting 45 to 50 mph and humidity values in the single digits. - 50 mph winds are expected over the southern mountains and the San Luis Valley, which may lead to blowing dust over the valley, blowing snow over the mountains, and travel concerns resulting in both cases. - Showers will be possible north of Highway 50 and west of I-25, with thunderstorms mainly across the Pikes Peak region. - A Freeze Watch remains in place for El Paso and Kiowa counties tonight, and frost may be possible for other portions of the plains as well. - Cooler and wetter weather is expected for all areas tomorrow and Wednesday. && .SHORT TERM /THROUGH TONIGHT/... Issued at 105 AM MDT Mon May 18 2026 For the plains..The elusive cold front has sagged back south since sunset, and is now sitting between Springfield and Campo across Baca County. This front and where it ends up again this afternoon will be the driving factor in today's forecast across the plains once again. North of the front and west of I-25, stratus has begun to develop up against the terrain as of midnight. USAFA is reporting ceilings down to 2,000ft, and the Colorado Springs airfield is starting to see lower scattered decks as well. Models continue to suggest that rain will be possible as upslope continues across the mountains/plains interface throughout this morning. Thunderstorms will be possible across the Pikes Peak region again this afternoon, though severe development is not expected. That said, lots of shear will present over the region today, so if any areas clear out and warm up, chances for a stronger storm or two may be possible, especially over the higher terrain of the Pikes Peak region. The main forecast concern on our plains today though will be our high end Red Flag Warning across our southern plains. Las Animas and Baca counties are both included in this warning, and southern portions of Bent and Prowers counties may see periods of critical conditions as well depending on how far north/east the front gets shoved this afternoon. Over these areas, single digit relative humidity values and southwest wind gusts of 45 to 50 mph are expected. The strongest winds and lowest humidities will be over Baca County this afternoon, which will lead to the possibility for extreme fire behavior for any new or existing fires today. Please use extra caution and take care not to start a wildfire today. One last note for the plains, gusty winds over our southeast plains may also lead to blowing dust and hazardous travel conditions. Once the sun sets, the front *finally* pushes itself completely southwards, allowing all areas to cool and moisten through the overnight hours. This will put an end to fire weather concerns for a few days. Overnight lows will be chilly in our post frontal airmass though, and areas north of Highway 50 may see hard freeze conditions by Tuesday morning. El Paso and Kiowa counties are both under Freeze Watches for tonight through early Tuesday morning, and temperatures down into the upper 20s will be possible. Another tier of counties or two may also see the potential for frost depending on clearing through the overnight hours. For the high country and the San Luis Valley..Models bring the trough axis through our southern mountains between 9 AM and Noon or so, which will be the windiest timeframe for the San Juans, the San Luis Valley, and the Sangres. The NBM continues to be the only outlier suggesting high wind criteria, so have continued to trend towards other model consensus, which keeps winds below warning levels across the area. The San Luis Valley is likely to see gusts upwards of 50 mph or so though, especially if any showers survive off the mountains and help to enhance gusts coming down the terrain. Areas of blowing dust are likely across the Valley today, especially with any localized stronger winds from decaying showers. Over the mountains, a quick 2 to 4 inches of wind driven snow will be possible for the San Juans and the central mountains. Though totals will be low, degraded visibility and hazardous travel conditions may be possible from blowing snow, especially over mountain passes. Snow comes to an end for both range by around midnight or so at the latest. && .LONG TERM /TUESDAY THROUGH SUNDAY/... Issued at 105 AM MDT Mon May 18 2026 Tuesday and Wednesday.. The front is finally through us and will stay through us for Tuesday and Wednesday. We stay in southwest flow aloft as messy troughing sits out west. This pattern will keep temperatures cooler than normal, and it will keep precip chances over us as well. Models bring shortwave energy through the trough and over us on Tuesday, which will help to develop weak showers and thunderstorms over the high country on Tuesday afternoon, and better chances for widespread rain on the plains overnight Tuesday and into Wednesday. Daytime highs look to stay in the 60s both days, with decent chances for precipitation both days. Thursday Onwards.. Models are not in great agreement about the pattern late week onwards, but the general consensus suggests some type of northwest flow with a trough passing to our north. This looks to bring temperatures back into the near normal range for Thursday and Friday, with warmer than normal temperatures by the weekend. Chances for showers and thunderstorms will remain in the forecast nearly every afternoon, especially across the high country. && .AVIATION /00Z TAFS THROUGH 00Z TUESDAY/... Issued at 1056 PM MDT Sun May 17 2026 KCOS and KPUB: MVFR to IFR conditions are expected through the majority of this TAF period due to lowered ceiling heights. With that said though, both KCOS and KPUB, but especially KPUB, will have a period of VFR condition ceiling heights during Monday afternoon. Looking at winds, they are expected to remain around and less than 10 knots tonight, though will quickly increase heading into the late morning and early afternoon hours as a potent storm system swings over the region. Winds are expected to remain elevated then into Monday evening, though will slowly start to lessen in magnitude. Otherwise, dry conditions are expected tonight, though KCOS may experience drizzle to light rain as upslope winds develop. Then during the early afternoon hours, a band of showers and thunderstorms is expected to push eastward off of the higher terrain and across the TAF sites, bringing periods of lower visibility. KALS: VFR conditions are expected over the next 24 hours, though a brief period of MVFR conditions will be possible Monday morning into the afternoon hours due to blowing dust within the San Luis Valley. Looking at winds, they will remain around 10-13 knots tonight, and increase quickly early Monday morning as a potent storm system passes over. In addition, showers may push eastward off the higher terrain and across the San Luis Valley, and a shower impacting the TAF site can not be ruled out. Otherwise, dry conditions will prevail, with mid to high level clouds persisting into Monday afternoon, and then starting to clear Monday evening. && .PUB WATCHES/WARNINGS/ADVISORIES... Freeze Watch from late tonight through Tuesday morning for COZ084-085-095-096. Red Flag Warning from 11 AM this morning to 8 PM MDT this evening for COZ230-233-237. && $$ SHORT TERM...EHR LONG TERM...EHR AVIATION...SIMCOE  659 FXUS65 KREV 180705 AFDREV Area Forecast Discussion National Weather Service Reno NV 1205 AM PDT Mon May 18 2026 .KEY MESSAGES... * Expect widespread freezing to near freezing temperatures this morning and again Tuesday. * A ridge builds back into the region by mid-week, allowing for warmer and drier conditions into the weekend. && .DISCUSSION... We tied a snowfall record at the Reno Int'l Airport today with officially a trace of snow, thanks to the cold frontal passage today. Expect a very cold morning today with lows near to below freezing for much of the area. Overnight lows rebound a bit Tuesday morning, but will remain on the chilly side. As for today, expect breezy afternoon winds with highs back to the mid 60s (valleys) and upper 50s (Sierra). We remain in a troughing upper-level pattern, with a low sitting off the coast of Baja California and high pressure building off the coast of the PacNW. This will allow for weak pressure gradients aloft, letting us slowly warm up through the week (as the ridge progresses eastward) with light and typical diurnal winds. Dry conditions will also accompany the warming trend. Looking towards the holiday weekend, there's a ~40% chance to see highs above 90 degrees in Reno and ~40% chance to see over 80 degrees in Tahoe. Shower chances look slim to none for the weekend as well. -Giralte && .AVIATION... VFR conditions expected for all terminals today with breezy east/northeasterly afternoon winds (gusts up to 20 kts), albeit not nearly as strong as the winds yesterday. -Giralte && .REV Watches/Warnings/Advisories... NV...Lake Wind Advisory until 5 AM PDT early this morning NVZ002. CA...Lake Wind Advisory until 5 AM PDT early this morning CAZ072. && $$  192 FXUS66 KMFR 180712 AFDMFR Area Forecast Discussion National Weather Service Medford OR 1212 AM PDT Mon May 18 2026 .DISCUSSION...The weather will be quiet with little impact as dry and stable conditions persist this week. With near unanimous agreement across the model suites, forecast confidence is high through Friday with upper level ridging gradually building into our area from the west. High pressure will remain anchored offshore through Wednesday, then build slightly eastward for additional warming on Thursday and Friday, when daytime highs expected to be around 10 or 15 degrees above normal for mid to late May. Slight cooling is possible next weekend or early next week, with a trough expected to move into western Canada. The majority of ensemble members keep the moisture associated with a couple of cold fronts well north of our area, but the second front around Memorial Day could be strong enough and near enough for a marine push and chance of showers for Coos and Douglas counties northward. && .AVIATION...18/12Z TAFs...Some marine stratus is forming near Cape Blanco this evening and the models have some of that spreading into Roseburg overnight. The boundary layer in some of the models do hint at stratus forming in the Umpqua Basin overnight with IFR ceilings developing for a few hours. Otherwise, those should clear out as we mix out into the day. VFR will prevail in all other areas for the next 24 hours. && .MARINE...Updated 1200 AM PDT Monday, May 18, 2026...A thermal trough will bring a typical pattern of gusty north winds and steep to very steep seas over the coastal waters much of this week. Winds will be strongest and seas will be highest during the afternoons/evenings. Through this stretch, very steep seas of 10- 12 ft are most likely south of Cape Blanco with steep seas (6-9 ft) north of Cape Blanco. Ensembles indicate winds will strengthen Wednesday into Thursday with a potential (50-70% chance) for gales across portions of the southern waters (especially from around Gold Beach south). && .MFR WATCHES/WARNINGS/ADVISORIES... OR...CA...None. PACIFIC COASTAL WATERS...Hazardous Seas Warning until 11 PM PDT Tuesday for PZZ356-376. Small Craft Advisory until 11 PM PDT Tuesday for PZZ350-370. && $$  273 FXUS64 KSJT 180714 AFDSJT Area Forecast Discussion National Weather Service San Angelo TX 214 AM CDT Mon May 18 2026 ...New SHORT TERM... .KEY MESSAGES... - Above normal temperatures expected through Monday. - Severe Storms possible Tuesday afternoon and evening. - Medium to High (30-80%) chances for showers and thunderstorms from Tuesday evening through Friday. && .SHORT TERM... (Today and tonight) Issued at 202 AM CDT Mon May 18 2026 Another breezy day with gusty south winds, particularly in the Big Country, with a surface low in the Panhandle and lee trough in West Texas. While the CAMs are mainly dry with a cap aloft, the NAM nest does develop a few isolated showers and thunderstorms in the Big Country this afternoon, but they are brief, only a couple hours. Still, if a storm does develop, it could become severe. Otherwise low clouds developing over the region will break up midday. Highs could reach 100 along a dryline from Sterling City to Sweetwater and Roby, but most areas will see upper 80s to lower 90s. There is the potential for thunderstorm late tonight in the Big Country as a cold front moves in toward daybreak into Haskell and Throckmorton counties. Very mild overnight with lows in the lower 70s, as low level moisture with dew points in the upper 60s to lower 70s continues to move up from the Gulf. This will also bring hazy conditions particularly in the mornings. && .LONG TERM... (Tuesday through Sunday) Issued at 102 AM CDT Mon May 18 2026 A trough remains in place across the Four Corners region on Tuesday and we will continue to see embedded disturbances within the flow aloft. Meanwhile, a pronounced dryline will be sitting just to our west again. This will combine with a cold frontal boundary moving into our area sometime on Tuesday morning into early afternoon. The combination of these three features will allow for more substantial support for thunderstorm development across the region. Rain chances will therefore be high (70-80%) on Tuesday. It still remains a bit uncertain how far south the frontal boundary will move into western Central Texas. This boundary appears to stall across the Concho Valley, which would help to prolong the rain chances. Conditions are favorable for this activity to be strong to severe as it moves through on Tuesday. In fact, we are indeed outlooked in a Slight Risk for severe weather by the Storm Prediction Center. The main hazards with this activity will be large hail and damaging winds. By the time Wednesday rolls around, another low pressure strengthens across the southwestern U.S. and starts moving to the east. This will provide another round of support for rain and thunderstorm development. High rain chances (80% chance) will be in place for Wednesday. The previous rainfall from Tuesday could saturate soils to some degree. As a result, locations that receive multiple rounds of rain will see increased risk of flood related concerns on Wednesday. The Weather Prediction Center has outlooked our area for a Slight Risk (15 to 40% chance) of Excessive rainfall leading to localized flash flooding for Wednesday. The long range models continue to show a disturbed weather pattern in place as this system moves east for the later half of the work week. This leaves a high rain chance (80%) in place for Thursday. Some remnants may linger into Friday, however, lower chances (30- 40%) will be in place for Friday. All of this activity from Tuesday onward will have to be monitored closely for future updates regarding the severe weather and excessive rainfall (flash flooding) potential. Please check back for future updates and ensure you have multiple ways to receive any watches or warnings that may be issued. && .AVIATION... (06Z TAFS) Issued at 1229 AM CDT Mon May 18 2026 Breezy south winds continue with winds up to 30 kts at KABI and 20-25KTS farther south. MVFR stratus had already developed over southern terminals and will spread north to KSJT and KABI overnight. Stratus will rise or scatter out to VFR midday to early afternoon. && .PRELIMINARY POINT TEMPS/POPS... Abilene 93 73 87 64 / 20 20 80 70 San Angelo 94 72 93 63 / 10 20 70 70 Junction 90 73 91 65 / 10 0 60 80 Brownwood 89 72 88 64 / 10 10 70 70 Sweetwater 99 72 88 62 / 20 20 80 60 Ozona 93 72 90 64 / 10 0 60 60 Brady 88 72 89 65 / 10 10 70 80 && .SJT WATCHES/WARNINGS/ADVISORIES... None. && $$ SHORT TERM...04 LONG TERM....41 AVIATION...04  392 FXUS63 KIWX 180716 AFDIWX Area Forecast Discussion National Weather Service Northern Indiana 316 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 with a mostly unidirectional wind profile again, damaging winds appear the most likely threat. 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 /06Z TAFS THROUGH 06Z TUESDAY/... Issued at 117 AM EDT Mon May 18 2026 VFR conditions will continue through midday with the only concern being some marginal LLWS as the low level flow begins to ramp up somewhat. A decaying MCS out of Iowa, Missouri, and Illinois will be the focus for potential strong to severe storms today. This complex is expected to weaken over Illinois this morning and then reintensify across northern Indiana around 18Z. Breezy southerly wind 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  412 FXUS63 KMQT 180717 AFDMQT Area Forecast Discussion National Weather Service Marquette MI 317 AM EDT Mon May 18 2026 .KEY MESSAGES... - Showers and thunderstorms exit the U.P. this morning with isolated to scattered showers and possibly a thunderstorm this afternoon. - Another round of showers and thunderstorms is expected tonight. Some of the storms could be severe, especially over the southern half of the U.P. Heavy rainfall is also possible. - Warmer than normal temperatures Monday, followed by cooler than normal temperatures for the rest of the week. && .DISCUSSION... Issued at 317 AM EDT Mon May 18 2026 Early this morning satellite water vapor imagery and RAP upper level analysis showed deep troughing over the western U.S. with southwesterly flow over the plains into the Upper Great Lakes. Satellite and radar showed widespread convection from KS up to northern WI ahead of frontal boundary. The storms were clustered over NW WI and the western U.P., close to a sfc low pressure that was tracking northeast into the area. Convection remained elevated, above the cooler easterly flow near the sfc and strong stable layer. SPC Mesoanalysis showed mucape of 500-1000 J/kg with effective shear of 20-30kt over the western U.P. which was helping to maintain thunderstorms pushing into the area but overall there was a weakening trend as cells crossed into the U.P. Temperatures were warming up a bit overnight as southeasterly flow strengthened with most locations in the upper 40s to low 50s. Showers and thunderstorms will continue to move through the western U.P. through this morning. Conditions will remain borderline for strong to severe thunderstorms, mucape ~1000 J/kg and effective bulk shear 20-30kt. The most likely hazard is hail but cant rule out isolated strong winds. These storms will move through parts of the north-central U.P. with more isolated to scattered showers and thunderstorms over the rest of the U.P. PWATs are in the 1.25-1.5" range, exceeding the 95th percentile from climo, thunderstorms will be capable of producing heavy rainfall. While scattered showers and an isolated thunderstorms will be possible the afternoon, mainly for the central and eastern U.P., most of the day is expected to be fairly quite with respects to thunderstorm activity due to strong capping and little in the way of large scale ascent. Should a storm manage to form and root itself at the surface it could become severe with cape to around 1500 J/kg and shear of ~40kt but the probability is very low. Southerly flow will increase and despite cloud cover expect temperatures to warm into the 60s and 70s. A lake breeze (Lake Superior) will form by early afternoon bringing falling to the lakeshore areas. The lake breeze / cold pool will expand inland through the remainder of the afternoon, further limiting the prospects for thunderstorm development. Tonight, a second low pressure will track north into the U.P. bringing another round of showers and thunderstorms. Models continue to trend downwards with respects to instability with href mean mucape of 500-1000 J/kg over much of the U.P. though areas in the south will see a bit more robust instability to around 1500 J/kg. Notable is also the downward trend in mid-level lapse rates in the models over the last several runs. 0-6km bulk shear is around 40kt so there is still the potential for strong to severe thunderstorms, especially over the southern U.P. SPC continues to include the CWA within their 15% risk region (slight risk), with primary hazards being large hail and damaging winds. WPC also continues to maintain a marginal risk for flash flooding with this second wave. Showers and gusty winds will linger Tuesday as the surface low and trough aloft push through the region. Thunderstormpotential looks to be isolated to the east in the morning. Sprawling high pressure builds in by evening, keeping the region dry through at least Friday morning. Daytime highs Wednesday look to peak in the 50s south and west, and 40s north-central and east. Thursday and Friday will trend back toward normal 60s, but the east may only top out in the 50s both days. && .AVIATION /06Z TAFS THROUGH 06Z TUESDAY/... Issued at 117 AM EDT Mon May 18 2026 Poor flying conditions continue through the period as we remain under the influence of a warm front that stalls out over the area during the daytime today. This will keep cigs low (mainly LIFR), with vis being a problem during mainly the overnight hours via BR/FG. That being said, the SHRA/TSRA seen over the terminals the next 24 hours will help to keep vis and cigs down as well. We could see an improvement to as high as MVFR over SAW this afternoon as the winds turn from S/SW to N/NE'rly. That being said, expect a return to LIFR conditions by the evening over SAW. Expect an hour or two and a few more hours of LLWS to return to IWD and SAW early this morning in the warm air regime as the low's center moves into Lake Superior. With the low's passage today, expect the winds across the terminals to shift from the E/SE early this morning to SW later this morning; expect a shift to the N/NE by late this afternoon. && .MARINE... Issued at 224 PM EDT Sun May 17 2026 Guidance continues to bring a low pressure into the Great Lakes Monday night, resulting in a tightening pressure gradient today and cold air advection Tuesday behind the low. The former will support a period of northeasterly gales in the western portions of Lake Superior this afternoon and evening. Shower and thunderstorm chances increase tonight, then linger until the low passes Tuesday morning. The first wave comes tonight across the east and then the west late tonight, both potentially lingering into Monday morning. Strong to severe storms can't be ruled out, the lack of effective shear within the cloud layer suggests the risk is marginal. The next organized cluster lifts through Monday night preceded by a warm and moist airmass. This will again support strong to severe storm potential and rainfall may be the trigger needed for overnight fog. In the wake of the low Tuesday, a second period of gales looks possible across eastern Lake Superior; although, ensemble guidance suggests the probability in the east being 25% or less. Once the winds settle Tuesday night/Wednesday, light winds are favored through at least Friday morning. && .MQT WATCHES/WARNINGS/ADVISORIES... Upper Michigan... None. Lake Superior... None. Lake Michigan... None. && $$ DISCUSSION...JTP/NL AVIATION...TAP MARINE...JTP  438 FXUS61 KOKX 180719 AFDOKX Area Forecast Discussion National Weather Service New York NY 319 AM EDT Mon May 18 2026 .WHAT HAS CHANGED... No significant changes, with hot weather expected thru Wed. && .KEY MESSAGES... 1) Summerlike temperatures through Wednesday 2) A cold front moves across Wednesday bringing showers and thunderstorms. Brief gusty winds and locally heavy rain possible. 3) Much cooler airmass expected Thursday into the holiday weekend. 4) Cold water safety concerns continue this week with good boating weather, and water temperatures still in the 50s. && .DISCUSSION... .KEY MESSAGE 1... No major changes to the hot fcst thru Wed. Kept with the previous trend of going a bit blw the NBM which is believed to be too warm. Went with a 50/50 blend of the MAV and NBM to accomplish this. The shallow backdoor cold front looks to have little impact on temps today aside from ern areas and LI, where onshore flow may limit highs a bit. Otherwise the hot airmass continues to build in. Depending on where the numbers end up today, there is a chance some of the usually warmer spots may need a heat advy based on the two-day 95 degree criteria. In addition, temps could spike on Wed ahead of the front. Guidance often has a tough time getting hot enough invof a front, especially a few days out. Despite that bias, the MAV/NBM blend still has a high of 94 for KNYC on Wed. .KEY MESSAGE 2... It looks increasingly likely that a cold fropa will occur during the day on Wed. The actual timing will be critical. Low moisture but sufficient instability and no CIN should allow for tstms to develop invof the front assuming a daytime passage. The best upr support is to the north, but there will be falling heights nonetheless. Primary severe threat based on the setup appears to be downburst winds with relatively high based storms attm. DCAPE in the NAM supports this with peak values around 1500J/kg modeled. There could be some hail as well with the dry air entrainment. .KEY MESSAGE 3... Mid level ridge suppressed for late week into the holiday weekend. At the surface, high pressure moves in from the Great Lakes Thursday but then moves northward into Northern New England and eventually the Canadian Maritimes Friday into the holiday weekend. Max temperatures forecast decrease by near 15 to 20 degrees for Thursday compared to the previous day. Max temperatures are in the upper 60s to lower 70s Thursday. Cooling trend continues Friday with high temperatures forecast mainly in the mid to upper 60s and then just low to mid 60s for most locations on Saturday. Overall, the low level flow will become more easterly. Along with that aside from Thursday and Friday which are forecast to be mainly dry, there will be an increasing chance of showers heading into the holiday weekend with high pressure getting farther away and low pressure approaching from the south and west. .KEY MESSAGE 4... Cold water safety concerns this week as water temperatures remain in the 50s. The cold water temperatures can quickly cause hypothermia and physical incapacitation to anyone suddenly immersed in the water. Anyone going out on small boats, canoes or kayaks should plan accordingly and use extreme caution to avoid this threat. && .AVIATION /06Z MONDAY THROUGH FRIDAY/... Weak high pressure over the area early this morning will give way to weak backdoor cold front dropping down along the New England coast and into the area later this morning. The front will quickly lift back to north as warm front later in the afternoon. VFR through the TAF period. Light winds overnight will vary from SW to variable, becoming E/SE during the morning hours, mainly after 09Z. Winds will gradually veer to a more southerly direction late morning into the afternoon, increasing to around 10kt with a some locations G15-18kt. KLGA is expected to be NE-ENE during the morning and early afternoon hours before veering to more southerly flow. KBDR also could hang on to an E wind into the afternoon, ...NY Metro (KEWR/KLGA/KJFK/KTEB) TAF Uncertainty... Gusts may be more occasional Monday afternoon. Winds may also be more to the left of the current forecast Monday afternoon. This will depend on how much the area can heat up to mix down a more SSW direction. .OUTLOOK FOR 06Z TUESDAY THROUGH FRIDAY... Late Monday Night: VFR. Tuesday: VFR. S/SW winds 10-15g20-25kt into eve. Isolated thunderstorm potential afternoon into early eve, mainly north of NYC terminals with brief MVFR or lower possible. Wednesday: VFR, giving way to possible MVFR or lower with potential showers and thunderstorms. Showers likely afternoon into eve with a chance of thunderstorms. S/SW winds 10-15g20-25kt day into eve. Peak gusts to near 30 kt possible. NW windshift in the evening. Thursday-Friday: MVFR or lower possible with a chance of showers. Detailed information, including hourly TAF wind component forecasts, can be found at: https:/www.weather.gov/zny/n90 && .MARINE... Winds and seas will remain blw SCA lvls today. Winds will increase tngt, with SCA cond possible on Tue, especially on the ocean. The threat for SCA winds and seas continues on Wed as a cold front passes, then winds and seas are modeled to remain blw advy lvls Thu and Fri. There could be some strong tstms invof the cold front on Wed. Cold water safety concerns this week as water temperatures remain in the 50s. The cold water temperatures can quickly cause hypothermia and physical incapacitation to anyone suddenly immersed in the water. Anyone going out on small boats, canoes or kayaks should plan accordingly and use extreme caution to avoid this threat. && .CLIMATE... Record High Temperatures: May 19: KEWR: 98/1962 KBDR: 89/2017 KNYC: 99/1962 KLGA: 96/2017 KJFK: 92/2017 KISP: 89/2017 Record High Minimum Temperatures: May 17: KEWR: 68/2015 KBDR: 60/2025 KNYC: 70/1906 KLGA: 68/1965 KJFK: 63/1965 KISP: 62/2015 May 18: KEWR: 74/2017 KBDR: 66/2017 KNYC: 75/2017 KLGA: 80/2017 KJFK: 65/2017 KISP: 63/1977 May 19: KEWR: 67/1986 KBDR: 66/2017 KNYC: 68/1986 KLGA: 68/2017 KJFK: 67/2017 KISP: 65/2017 May 20: KEWR: 72/1996 KBDR: 61/2019 KNYC: 74/1996 KLGA: 77/1996 KJFK: 63/1996 KISP: 62/1996 && .OKX WATCHES/WARNINGS/ADVISORIES... CT...None. NY...Air Quality Alert from 11 AM this morning to 11 PM EDT this evening for NYZ069>075-176-178. NJ...None. MARINE...None. && $$  423 FXUS63 KDMX 180718 AFDDMX Area Forecast Discussion National Weather Service Des Moines IA 218 AM CDT Mon May 18 2026 .KEY MESSAGES... - Enhanced Risk (level 3 of 5) of severe storms this evening. Tornadoes, damaging winds, and large hail are possible as a line of storms moves west to east across the state. - Cooler and dry through the middle of the week. && .SHORT TERM /THROUGH TONIGHT/... Issued at 218 AM CDT Mon May 18 2026 Showers and thunderstorms continue to push east across Iowa early this morning. While the line of storms was initially robust in western Iowa last evening, producing damaging wind gusts and tornadoes, early this morning the cold pool has surged out ahead of the storms and weakened the storms significantly. Drying on the backside of the decaying MCS has resulted for wake low type winds to develop, with recent gusts of 40-50+ mph occurring. We will be watching this closely through the morning as a similar set up yesterday resulted in even stronger gusts. So far those have yet to materialize and this line is more progressive than yesterday's storms in southern Iowa. No hydro problems have been identified with the storms overnight tonight with the progressive nature of the line helping to reduce residence time over any single location. These storms are tied to a surface low currently centered over north central Iowa and south central Minnesota that will continue to move east this morning and through today. Meanwhile the primary surface low is centered across the panhandle of Oklahoma and southwest Kansas early this morning. This will eject northeast today as the upper level trough finally kicks east. This will serve as the impetus for convective initiation once again this afternoon, and will be the final round in this four day stretch of severe weather across Iowa. Evolution and expectations for severe storms will be outlined below, however it is important to note first that the ongoing/diminishing MCS across Iowa this morning will impact the evolution of storms later today. Storm strength this afternoon into Iowa will depend on how quickly the atmosphere can recover and how far north theta e advection can surge back north into the state after the cold pool shoves that boundary south. CAMs indicate that the atmosphere should recover by late this afternoon with soundings largely uncapped across most of central and southern Iowa. This uncapped environment has 3000-3500+ J/kg of SBCAPE along with well curved hodographs through the low to mid levels. SRH values of 300-400 m2/s2 in the 0-3 km layer, 250-300 m2/s2 in the 0-1 km layer, and 200+ m2/s2 in the 0-500 m layer will be more than sufficient to maintain rotating updrafts through the mid levels and helicity for potential tornadogenesis in the low levels. The streamwise factor is also around 0.03-0.04 for storms to ingest efficiently. While shear/rotational factors are certainly in place for tornado genesis, low level instability is somewhat lacking. SBCAPE is quite high, but much of that is through the mid levels with steep 8C/km lapse rates. Low level 0-3 km CAPE is much lower at under 50 J/kg. Less low level stretching could help to limit tornadogenesis, but certainly cannot be counted on in an otherwise volatile environment. Storms are expected to initiate in eastern Nebraska around 21z and move into southwest Iowa around 22- 00z. The line will continue to push east across the state. The low level jet will strengthen after 00z, helping to maintain storms into central Iowa through 06z. Storms are expected to diminish in strength as they move east around and after 06z tonight. There is deep moisture transport into the area ahead of the upper level trough with PWATs of 1.5-1.75" across the area which should support efficient rainfall across the area this evening. The good news here is that the line of storms remains progressive and should limit most hydro concerns. Even so, pockets of 2-3" may be possible in southern Iowa where storms are more initially discrete/clusters before growing upscale and lining out across central Iowa. Given multiple rounds of precipitation over the last several days, capacity has diminished some, though most areas should still be able to handle the expected QPF. Primary areas of concern would be any heavy rain pockets that set up over towns. Widespread flash flooding is not anticipated to be a concern. && .LONG TERM /TUESDAY THROUGH SUNDAY/... Issued at 342 PM CDT Sun May 17 2026 A much needed break from the active weather stretch begins on Tuesday as a high pressure nudges into the region later Tuesday into Wednesday. Mid-level winds behind the departing system Monday night also turn out of the north to northwest ushering in cooler temperatures with highs in the 50s to 60s on Tuesday through Thursday and lows Wednesday and Thursday mornings in the upper 30s to 40s. Winds on Tuesday will remain elevated through much of the daytime with a tight pressure gradient still in place with sustained winds out of the northwest 15-25 mph, and gusts to near 30 mph in the northwest. Showers and thunderstorms then return to the forecast from later Thursday into Friday as an upper trough crosses the Central Plains with a developing surface low reaching towards the area into Friday. Additional details to come in the next several days. && .AVIATION /06Z TAFS THROUGH 06Z TUESDAY/... Issued at 1109 PM CDT Sun May 17 2026 Storms continue to push through central Iowa with precipitation slowly sagging southeast with time through the overnight hours. Localized visibility drops have occurred with sites down to MVFR or IFR at times. Similarly, ceilings have fallen to MVFR, IFR, and even LIFR. Behind the storms, MVFR ceilings, localized IFR, may move into portions of especially northern Iowa into Monday morning. Additional storms are forecast on Monday and have started with some prob 30 groups but refinements are likely. && .DMX WATCHES/WARNINGS/ADVISORIES... None. && $$ SHORT TERM...Hagenhoff LONG TERM...05 AVIATION...05  421 FXUS63 KIWX 180718 AFDIWX Area Forecast Discussion National Weather Service Northern Indiana 316 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 /06Z TAFS THROUGH 06Z TUESDAY/... Issued at 117 AM EDT Mon May 18 2026 VFR conditions will continue through midday with the only concern being some marginal LLWS as the low level flow begins to ramp up somewhat. A decaying MCS out of Iowa, Missouri, and Illinois will be the focus for potential strong to severe storms today.This complex is expected to weaken over Illinois this morning and then reintensify across northern Indiana around 18Z. Breezy southerly wind 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  507 FXUS62 KTBW 180722 AFDTBW Area Forecast Discussion National Weather Service Tampa Bay Ruskin FL 322 AM EDT Mon May 18 2026 ...New DISCUSSION, AVIATION, MARINE, FIRE WEATHER... .KEY MESSAGES... - Above normal temperatures are expected each day through the next week. - Thunderstorms are expected to develop each day this week, mainly in the afternoon to early evening hours. - Severe to extreme drought conditions continue for most areas. && .DISCUSSION... Issued at 322 AM EDT Mon May 18 2026 Currently at the surface, the sub-tropical ridge of high pressure is centered east of the Carolinas, and will largely hold in place through the week, keeping firm control on the weather pattern for the area. With the ridge to the northeast of Florida, east and southeast flow will result in above normal temperatures with highs topping out in the upper 80s to mid 90s each day through the forecast period. This flow pattern will also bring chances of mainly afternoon and early evening showers each day, mostly along sea breeze and outflow boundaries. For today, a pocket of dry air will move west off the Atlantic into northern Florida, prohibiting significant rain chances for areas north of Interstate 4. For the southern half of the area, more favorable atmospheric moisture will result in scattered to numerous shower and storms this afternoon, with the highest rain chances close to the west coast with the sea breeze collision. Tuesday through Thursday, deeper moisture will wrap back into northern Florida from the Atlantic, allowing for isolated to scattered storm chances over the northern half of the forecast area, while deeper moisture to the south will bring scattered to numerous storms each afternoon, with the greatest storm coverage just inland of the west coast in the late afternoon. Late in the week and into the weekend, a frontal boundary will stall out north of Florida, shifting the sub-tropical ridge slightly east. This will result in the flow pattern becoming weaker and slightly more southeasterly, shifting the highest rain chances farther inland than what will be seen earlier in the week. && .AVIATION... (06Z TAFS) Issued at 322 AM EDT Mon May 18 2026 VFR conditions are expected to hold through the morning. Scattered to numerous showers and thunderstorms will develop this afternoon and evening, with the highest rain chances over southwest Florida around KRSW, KFMY, and KPGD, although the chance of thunderstorm disruptions at terminals farther north cannot be completely ruled out. Rain free and VFR conditions are expected to return by around 02-03z this evening. && .MARINE... Issued at 322 AM EDT Mon May 18 2026 High pressure will hold northeast of Florida through the week, with east and southeast flow continuing, turning onshore near the coast each afternoon with the sea breeze circulation. Winds and seas will generally hold less than headline criteria, although there is a chance for showers and thunderstorms moving west into the coastal waters each day during the late afternoon and early evening hours, causing locally higher winds and rough seas. && .FIRE WEATHER... Issued at 322 AM EDT Mon May 18 2026 A slightly drier air mass will shift west into northern Florida today, limiting rain chances north of Interstate 4 and dropping relative humidity to near critically low level this afternoon. South of I-4, humidity will be slightly higher, with scattered afternoon showers and storms. Moisture and humidity increases again on Tuesday, resulting in scattered to widespread showers and storms across the area in the afternoon. && .PRELIMINARY POINT TEMPS/POPS... TPA 92 75 92 75 / 20 10 50 10 FMY 93 74 93 74 / 50 20 70 20 GIF 92 72 91 72 / 20 0 30 10 SRQ 93 73 93 73 / 40 20 50 20 BKV 94 70 94 69 / 10 0 50 0 SPG 94 75 94 76 / 20 10 50 20 && Sea Breeze Thunderstorm Regime For Monday: 3 Sea Breeze Thunderstorm Regime For Tuesday: 3 For additional information on sea breeze regimes, go to: https://www.weather.gov/tbw/ThunderstormClimatology && .TBW WATCHES/WARNINGS/ADVISORIES... FL...None. Gulf waters...None. && $$ Fleming  647 FXUS65 KTWC 180727 AFDTWC Area Forecast Discussion National Weather Service Tucson AZ 1227 AM MST Mon May 18 2026 .SYNOPSIS... A storm system tracking to our north across the Great Basin will result in breezy conditions and below normal high temperatures across southeast Arizona today. High temperatures warm to near normal by Wednesday and remain there into next weekend. && .DISCUSSION... A low pressure system is currently in the Great Basin will keep our winds a tad elevated overnight tonight into early tomorrow morning with southwest winds at 10-20 mph with gusts up to 25 mph. Winds then increase to 15-25 mph with gusts up to 35 mph, with the strongest winds for areas south and east of Tucson. These elevated winds can lead to near critical fire weather concerns, more in the fire weather section. Outside of the winds, the sky can be a tad hazy today due to lofted dust from the stronger winds yesterday, but this will clear up as the winds decrease. Winds will begin to decrease in the early evening today. Once this system passes, there will be general troughiness lingering keeping us under dry, southwest flow into next weekend. This pattern will keep the area with milder weather with temperatures hovering right around normal into the weekend. && .AVIATION...Valid through 19/12Z. There will be periods of high level cirrus clouds AOA 20k ft AGL passing thru the area during the valid pd. SFC winds SWLY/WLY at 8-15 kts then increase to 10-20 kts with gusts to 30 kts return aft 18/16z with strongest winds areas south and east of KTUS including KDUG and KOLS. Aviation discussion not updated for TAF amendments. && .FIRE WEATHER... 20-foot southwest winds remain elevated today with speeds of 15-20 mph with gusts up to 35 mph as a weather system exits the region. RH values will be above critical levels at most locations today in the upper teens (or higher), although portions of Cochise, Graham, and Greenlee Counties may see critical fire weather conditions for an hour or so this afternoon. Dry conditions the next 7 days with high temperatures on Monday 4 to 10 degrees below normal, then warming to near normal by Wednesday and remaining there into next weekend. Min RH values today will range from 10-15 percent from Tucson east to 20-25 percent west of Tucson. Min RH values Tuesday into next weekend 6-16 percent in the lower elevations and 8-20 percent in the mountains. && .TWC WATCHES/WARNINGS/ADVISORIES... None. && $$ JT Visit us on Facebook, X, YouTube, and at weather.gov/Tucson  898 FXUS65 KABQ 180730 AFDABQ Area Forecast Discussion National Weather Service Albuquerque NM 130 AM MDT Mon May 18 2026 ...New SHORT TERM, LONG TERM, FIRE WEATHER... .KEY MESSAGES... Updated at 115 AM MDT Mon May 18 2026 - The threat of rapid fire spread continues today with the most critical to locally extreme fire weather conditions focused over eastern New Mexico. - Hazardous crosswinds will impact high profile vehicles along with lowering visibility due to blowing dust this afternoon. - Afternoon thunderstorm activity increases over eastern New Mexico Wednesday and Thursday. && .SHORT TERM... (Today through Tuesday) Issued at 115 AM MDT Mon May 18 2026 A stout 100-110kt H3 jetmax, sampled by the Reno WFO on the prior 00Z sounding, continues to dig south and southeastward over Area 51 northwest of Las Vegas, NV this hour. Southwesterly winds ahead of this system over AZ/NM continues to strengthen in response to this H5 low closing off and deepening over NV/UT this morning. Most of these winds remain aloft just above the surface but have and will continue to waffle up and down in altitude, at times reaching the surface in erratic fashion. The ABQ Sunport has seen some of these erratic wind speeds already tonight at times gusting to 30 mph before subsiding again. A day of strong winds gusting 30 to 45 mph, peaking in strength to 50 to 55 mph along and immediately east of the Sangre de Cristo Mts remains on track. Numerical model guidance continues to show the main jetmax and vortlobe rounding the southern periphery of the H5 low over northern NM by 12pm MDT today before quickly ejecting northeastward over the Great Plains late today and tonight. This timing just misses peak diurnal heating and mixing to fully realize the highest wind potential. As such, while it won't be surprising to see a few gusts reach high wind thresholds of > 58mph along the highest peaks of the Sangre de Cristo Mts and perhaps a stray spot along the northeastern highlands, confidence was not high enough to fully upgrade the High Wind Watch to a Warning with this forecast package. Wind Advisories were instead hoisted across the northeastern quadrant of the state from Taos and the Sangre de Cristo's eastward and from I-40 northward. Hazardous crosswinds for high profile vehicles and localized blowing dust threatening low visibility will be the main travel impacts this afternoon. Any precipitation associated with this system will barely skirt the far northern tier of the state along the CO border. Wind speeds quickly taper off past sunset this evening as the aforementioned H5 low opens and quickly exits the region. Left in its wake will be a potent cold front backing southward through eastern NM Monday night into Tuesday morning. Gusty northerly winds up to 25 to 35 mph will push in behind the front, aided by a quick 3hr 9-12mb increase in MSLP. This will be a concern for any fire suppression activities over eastern NM given the initial sudden wind shift. The good news is that winds will decrease further through Tuesday morning before shifting easterly then southeasterly over eastern NM. Drier southerly to southwesterly winds return to a good portion of the highlands, having never left western NM and the Rio Grande Valley Tuesday afternoon, but at a significantly lower speed relative to Monday. A few stray showers and perhaps a stray thunderstorm if any would favor the eastern slopes of the Sangre de Cristo Mts Tuesday afternoon. Otherwise, another dry day for many aside from the increase in humidity over eastern NM. && .LONG TERM... (Tuesday night through Sunday) Issued at 115 AM MDT Mon May 18 2026 Wednesday begins the long term with a tricky meteorological forecast over eastern NM. The aforementioned cold front that backs through eastern NM Tuesday will see winds veer southeasterly across eastern NM. The question however is whether or not return flow from the Gulf will bring in warmer air and higher dewpoints in the upper 50s into eastern NM Wednesday, or if the subtly drier continental airmass further north with its lower dewpoints in the 40s holds on? The warmer and higher moisture GFS solution would favor a higher instability and chances for subsequent afternoon thunderstorm activity along a sharpening dryline over eastern NM Wednesday afternoon. The more stable NAM solution would likely favor a blanket of low stratus loitering over eastern NM much of the day suppressing chances for afternoon convection. A middle ground compromise (deterministic Canadian solution) was chosen for this forecast package where the boundary b/w the higher moisture Gulf return flow and continental airmass is faded somewhere through east-central NM with some afternoon convection favored along the dryline along the highlands immediately east of the central mountain chain. While western NM stays high and dry, eastern NM will see low level moisture attempt to push westward again into parts of the Rio Grande Valley through the gaps of the central mountain chain. How much will likely depend on coverage and strength of any convective outflow boundaries occurring from any convective activity over eastern NM Wednesday evening. This will determine how widespread any afternoon convective activity will be over the eastern third of NM Thursday. Modest westerlies associated with a shortwave trough trekking eastward over WY/CO will shunt low-level moisture back east into the TX/OK Panhandles by Friday. This shuts down precipitation chances for much of eastern NM except the furthest northeastern corner in Union County. A subsequent cold front backing southward through eastern NM in the wake of the exiting shortwave trough will replenish moisture over eastern NM next weekend. This will return the two-faced pattern of weather over NM with western areas remaining high and dry with chances for afternoon thunderstorm activity over eastern NM. && .AVIATION... (06Z TAFS) Issued at 1122 PM MDT Sun May 17 2026 Strengthening southwesterly winds aloft across the region alongside decreasing surface winds will continue the threat of LLWS thru the night. This will steadily subside through the morning hours around dawn as southwesterly surface wind speeds begin to increase again. Strong southwesterly gusts will commonly reach 25 to 35 kts over the region with the weakest wind speeds relegated to far northwestern NM near KFMN. The strongest gusts of 40 to 50 kts will focus along and immediately east of the Sangre de Cristo Mts. Some patchy blowing dust could also reduce visibilities at some dust prone terminals Monday afternoon, including at KABQ and KROW. An Airport Weather Warning for gusts reaching or just surpassing 35kts may be required for KABQ as well Monday afternoon. Winds begin to taper off in earnest past 00Z Monday evening, with the exception of gusty northerly winds behind a cold front advancing southward along the NM/TX border Monday night into Tuesday morning. && .FIRE WEATHER... Issued at 115 AM MDT Mon May 18 2026 ...CRITICAL TO EXTREMELY CRITICAL FIRE GROWING PATTERN CONTINUES TODAY... Southwesterly to westerly winds strengthen in earnest this morning gusting 30 to 45 mph with peak gusts reaching 50 to 55+ mph along and east of the Sangre de Cristo's. The exception will be moderately weaker westerlies in far northwestern NM where a few stray showers may skirt the CO border. Otherwise, the winds will combine with widespread humidity falling to 10 to 15 percent with 6 to 11 hours of single-digit humidity in the lower Rio Grande Valley and eastern plains to produce widespread critical fire weather conditions. Extremely critical conditions will exist where the strongest winds coincide with the lowest single-digit humidity over east-central and northeastern NM. Winds quickly retreat from their peak speeds this evening with the exception of far eastern NM where gusty northerly to northeasterly winds behind an advancing cold front will bring a sudden wind shift late this evening and overnight into Tuesday morning. Timing of this sudden wind shift will be a main concern for any ongoing suppression activities through eastern NM. Otherwise, the good news is cooler temperatures and better recoveries heading into Tuesday once winds calm. Breezy to at times windy southwesterlies return Tuesday afternoon, pushing back this moisture toward TX and CO and producing elevated to locally critical conditions in portions of the Rio Grande Valley from Socorro to ABQ. A stronger westward push of low-level moisture pushes a dry line westward to or through the gaps of the central mountain chain into the Rio Grande Valley. This will create a dichotomy of dry elevated fire weather conditions over western NM each day with higher moisture and chances for afternoon thunderstorm activity across eastern NM Wednesday and Thursday. Central portions along the central mountain chain and the Rio Grande Valley will be in flux with likely good overnight recoveries with drying conditions during the afternoons. Friday sees drier westerlies punch eastward toward the TX line before higher low-level moisture returns to eastern NM next weekend. && .PRELIMINARY POINT TEMPS/POPS... Farmington...................... 68 39 75 43 / 20 0 0 0 Dulce........................... 64 30 73 37 / 50 0 0 5 Cuba............................ 67 37 73 42 / 0 0 0 0 Gallup.......................... 68 34 74 36 / 5 0 0 0 El Morro........................ 66 38 73 42 / 0 0 0 0 Grants.......................... 72 37 78 41 / 0 0 0 0 Quemado......................... 72 39 76 43 / 0 0 0 0 Magdalena....................... 76 47 78 51 / 0 0 0 0 Datil........................... 71 42 76 46 / 0 0 0 0 Reserve......................... 75 37 80 41 / 0 0 0 0 Glenwood........................ 80 41 84 44 / 0 0 0 0 Chama........................... 57 31 67 37 / 60 0 0 20 Los Alamos...................... 69 46 70 51 / 0 0 0 5 Pecos........................... 73 39 72 43 / 0 0 0 5 Cerro/Questa.................... 64 38 70 43 / 0 0 0 30 Red River....................... 54 32 61 35 / 0 0 5 40 Angel Fire...................... 62 26 63 31 / 0 0 10 40 Taos............................ 68 35 72 42 / 0 0 0 20 Mora............................ 69 37 70 42 / 0 0 0 30 Espanola........................ 77 43 80 49 / 0 0 0 0 Santa Fe........................ 72 45 73 49 / 0 0 0 0 Santa Fe Airport................ 76 43 75 47 / 0 0 0 0 Albuquerque Foothills........... 79 52 81 56 / 0 0 0 0 Albuquerque Heights............. 81 53 83 54 / 0 0 0 0 Albuquerque Valley.............. 82 49 85 52 / 0 0 0 0 Albuquerque West Mesa........... 81 50 83 53 / 0 0 0 0 Belen........................... 86 47 85 49 / 0 0 0 0 Bernalillo...................... 80 49 84 53 / 0 0 0 0 Bosque Farms.................... 83 46 85 48 / 0 0 0 0 Corrales........................ 81 49 84 52 / 0 0 0 0 Los Lunas....................... 83 46 85 49 / 0 0 0 0 Placitas........................ 77 50 79 55 / 0 0 0 0 Rio Rancho...................... 80 50 84 54 / 0 0 0 0 Socorro......................... 88 53 87 56 / 0 0 0 0 Sandia Park/Cedar Crest......... 73 46 77 50 / 0 0 0 0 Tijeras......................... 76 47 78 51 / 0 0 0 0 Edgewood........................ 76 44 78 48 / 0 0 0 0 Moriarty/Estancia............... 79 40 78 41 / 0 0 0 0 Clines Corners.................. 74 42 70 45 / 0 0 0 5 Mountainair..................... 78 45 79 47 / 0 0 0 0 Gran Quivira.................... 76 45 78 47 / 0 0 0 0 Carrizozo....................... 79 53 81 54 / 0 0 0 0 Ruidoso......................... 73 48 76 51 / 0 0 0 0 Capulin......................... 72 30 63 37 / 0 5 0 40 Raton........................... 76 35 68 40 / 0 0 0 40 Springer........................ 78 37 70 42 / 0 0 0 40 Las Vegas....................... 73 37 69 43 / 0 0 0 40 Clayton......................... 83 38 68 42 / 0 0 0 40 Roy............................. 78 40 69 43 / 0 0 0 40 Conchas......................... 88 46 77 48 / 0 0 0 40 Santa Rosa...................... 84 45 77 47 / 0 0 0 40 Tucumcari....................... 91 46 79 49 / 0 0 0 40 Clovis.......................... 89 46 80 50 / 0 0 0 10 Portales........................ 91 46 80 50 / 0 0 0 10 Fort Sumner..................... 88 47 82 50 / 0 0 0 40 Roswell......................... 92 54 86 57 / 0 0 0 20 Picacho......................... 83 51 84 51 / 0 0 0 5 Elk............................. 80 49 85 49 / 0 0 0 0 && .ABQ WATCHES/WARNINGS/ADVISORIES... Red Flag Warning from 9 AM this morning to 9 PM MDT this evening for NMZ104-106-109-121>126. Wind Advisory from 9 AM this morning to 8 PM MDT this evening for NMZ210-212>216-223-227>234. Wind Advisory from 5 AM early this morning to 8 PM MDT this evening for NMZ226. && $$ SHORT TERM...24 LONG TERM....24 AVIATION...24  136 FXUS63 KTOP 180735 AFDTOP Area Forecast Discussion National Weather Service Topeka KS 235 AM CDT Mon May 18 2026 .KEY MESSAGES... - Numerous severe storms are expected late this afternoon over north central Kansas, spreading across northeast Kansas this evening and overnight. Threats include very large hail (2-4+ inches in diameter), Damaging wind gusts to 80 mph, flash flooding, and tornadoes (a few strong). - A Flood Watch is in effect for all of northeast and north central Kansas where antecedent heavy rainfall has enhanced the threat for flash flooding this evening. - After cooler and dry conditions Tue. and Wed., storm chances return with the highest being on Thursday. Widespread severe probabilities are low at this time. && .DISCUSSION... Issued at 232 AM CDT Mon May 18 2026 Active early Monday morning as a decaying line of slow moving thunderstorms impacts portions of northeast and east central Kansas. Overall threat has shifted to heavy rainfall as hourly rainfall rates of 1 to 2 inches have been observed. Totals have currently ranged from 1 to 5 inches with the highest amounts focused over north central Kansas. As the low level jet wanes, activity is anticipated to dissipate by mid morning, leaving the stratus in place and potentially an outflow boundary in far eastern Kansas to MO. How quickly the atmosphere recovers in eastern Kansas is uncertain, potentially generating scattered severe storms by mid afternoon. Confidence in this scenario is somewhat bolstered by the last few runs of the HRRR/RAP, forming convection south of I-70 and east of I-35. Forecast soundings in vicinity of this outflow boundary exhibit strong low and mid level wind shear and elevated CAPE up to around 3000 J/KG. If this occurs, damaging wind gusts, large hail, and a few tornadoes cannot be ruled out earlier in the afternoon. Overall confidence for the above scenario is low-medium, owning to timing and location inconsistencies of current convection and where the boundary settles by midday. In terms of the main severe weather setup, no major changes were noted in forecast trends as the moderate severe risk from SPC remains centered from the Flint Hills region to the Kansas/Nebraska border. Negatively tilted upper trough axis across the Four Corners Region is anticipated to eject into the western high plains between 21Z-00Z. At this time, dryline/cold front is oriented southwest to northeast over north central Kansas as rich low level moisture raises dewpoints into the low 70s pooling just ahead of the stalled boundary. In addition clouds are anticipated to scatter out by late afternoon, resulting in SFC CAPE exceeding 5000 J/KG amid minimal inhibition. Strong convergence along the front is sufficient for discreet convection to form in the 3-5 PM timeframe over north central Kansas. Initial severe storms will be most intense in terms of very large hail (2-4+ inches diameter) and strong tornadoes, especially as the low level jet strengthens in the early evening. The strong tornado threat persists into the early evening with any discrete supercells. Bulk shear vectors parallel to the front suggest discrete cells transition to a line of storms around 7 PM. Main hazards with the squall line are damaging wind gusts to 80 mph , brief tornadoes along the leading edge, and large hail as they quickly translate east southeast through eastern Kansas. Forward propagating corfidi vectors are weak (20 kts) while PWAT values increase above 1.5 inches and low/mid level moisture saturates the column. Given the several inches of rainfall that occurred the last evening, decided to expand the Flood Watch to cover the entire forecast area through Tuesday morning. Estimated rainfall totals tonight range from 2 to 5 inches, increasing the likelihood for localized flash flooding. Activity exits into Missouri between 3 and 6 AM Tuesday. Much cooler airmass settles in behind the front Tuesday and Wednesday afternoons as highs only peak in the middle to upper 60s. Showers and isolated storm chances return by Thursday as broad upper troughing amplifies to the north and west. However, given the influence from sfc ridge to the northeast and lack of good return moisture, the overall severe threat is low. Better dynamics return by Friday evening, signaling the possibility for strong storms in the Kansas region. && .AVIATION /06Z TAFS THROUGH 06Z TUESDAY/... Issued at 1222 AM CDT Mon May 18 2026 VFR at terminals with a weakening line of TSRA impacting sites to start the forecast period. Storms will gradually weaken aft 08Z, clearing west to east through 13Z. Initial northwest winds behind an outflow boundary gradually veers back to the south by sunrise, gusting to around 30 kts during the daytime period. Added a PROB30 group for TSRA aft 00Z as a line of storms is likely to form west of sites before tracking southeast overnight along a fropa. && .CLIMATE... Issued at 234 AM CDT Mon May 18 2026 Record High Temperature Monday May 18 Record (Year) Forecast Topeka 94 (1975) 87 Concordia 94 (1967, 1988) 84 Record Warm Low Temperature Monday May 18 Record (Year) Forecast Topeka 71 (1911) 68 Concordia 72 (1911) 61 && .TOP WATCHES/WARNINGS/ADVISORIES... Flood Watch through Tuesday morning for KSZ008-KSZ009-KSZ010- KSZ011-KSZ012-KSZ020-KSZ021-KSZ022-KSZ023-KSZ024-KSZ034. Flood Watch from 9 AM CDT this morning through this evening for KSZ026-KSZ035-KSZ036-KSZ038-KSZ039-KSZ040-KSZ054-KSZ055- KSZ056-KSZ058-KSZ059. Wind Advisory from 9 AM this morning to 9 PM CDT this evening for KSZ035-KSZ036-KSZ037-KSZ038-KSZ054. && $$ DISCUSSION...22 AVIATION...22 CLIMATE...Griesemer  209 FXUS63 KGID 180736 AFDGID Area Forecast Discussion National Weather Service Hastings NE 236 AM CDT Mon May 18 2026 .KEY MESSAGES... - A handful of severe storms capable of producing large hail, damaging wind gusts or an isolated tornado will be possible between 3-8PM today. The severe threat will mainly be for places near and east of HWY-81. - A few showers, areas of drizzle and non-severe thunderstorms will be possible later this morning to afternoon across areas outside of the severe threat. - Highs, following the passage of a cold front today, will peak in the 50s and 60s for much of the area. A few north central Kansas locations as well as far southeast nebraska areas could see highs in the 70s. - The next chance of precipitation will come Wednesday night (40-50% chance). - Highs the rest of the week will stay in the 60s for Tuesday/Wednesday/Thursday, the low to mid 70s for Friday and the upper 70s to low 80s for Saturday. && .UPDATE... Issued at 235 AM CDT Mon May 18 2026 Today... Severe storms will again be possible across a few of the same locations that have observed severe weather across the past two days (Primarily north central Kansas and Nebraska locations east of HWY- 81). A persisting trough that has stalled out across the intermountain west region this past weekend will once more steer a southwesterly jet overtop of the Central Plains today. A cold front this morning resides across parts of central Kansas and eastern Nebraska. This feature will become the day's primary storm forcing mechanism. The cooler and drier airmass behind the front should dampen the severe weather potential for much of our northwest half of the area including our central/Tri-Cities area (though showers and weak storms may still be possible). Highs in response to the gusty cool air advecting winds behind the front should also struggle to break out of the 50s to low 60s beyond a few north central Kansas and far southeast Nebraska locations. As far as the storms go this afternoon (between 3-8PM), all convective types will be possible with all hazards in the mix (large hail, damaging winds, and a few tornadoes). A warm, moist and unstable airmass ahead of the cold front will offer plenty of energy to allow storms to erupt and quickly become severe (up to 1,500- 4,000J/kg of MUCAPE). Southerly winds ahead of the front and underneath the southwesterly jet will provide enough shear for a few supercells to spin, though the strong frontal forcing should prevent storms from staying isolated for too long (squall/MCS will be favored). With how far the cold front has advanced today, its is unlikely for the severe storms to impact much of our local area (mainly for areas near and east of HWY-81 and for a few north central Kansas locations). Only a southeast sliver of the area (areas southeast of a line from York, NE to Osborne, KS) has been included in a slight (level 2 of 5) or enhanced (level 3 of 5) severe weather outlook. Though the severe storms are expected to mainly stay concentrated to the southeast of most of the area, widespread drizzle, light rain and some non-severe thunderstorms will still be possible for part of the morning and afternoon hours today. Up to 0.5" of precipitation may be possible. Tuesday & Wednesday... Cooler temperatures will take over on Tuesday and Wednesday following the passage of the cold front today. Highs are forecast to remain in the 60s with overnight lows in the 30s to low 40s. The formation of frost may have to be monitored closely across a few locations closer to the Nebraska sandhills Tuesday night as winds look to calm overnight. These calming winds will be a result from the high pressure center swooping in near the middle of the week. The next chancefor precipitation will not come until Wednesday night (40-50% chance) as a weak shortwave disturbance potentially comes pivoting out of the Rockies. && .DISCUSSION... Issued at 1235 PM CDT Sun May 17 2026 The main concern in this forecast revolves around severe convection today and on Monday. Currently, most of the area is in the warm sector, with a cold front pushing in from the west, and a dryline/triple-point expected to push in from the southwest this afternoon. The eastern half of the area should be quite unstable by late afternoon, the MLCAPE values likely in the 2000-4000 J/kg range. If anything, CAMs have trended a bit further west with storm initiation...possibly as early as 4pm...but becoming more likely by around 5pm in the Highway 281 corridor. Strong deep-layer shear will be supportive of supercells, potentially merging into multiple line segments later into the evening hours. Confidence in coverage is highest in northern parts of the area and southern portions of the area, areas to the south and east of Hastings may not Generally the entire area near/east of Highway 281 has some threat for tornado today, although the highest risk is expected to be north and east of Grand Island where low-level shear is maximized. Sig-tor parameter (STP) values of 5-7+ are forecast by the RAP/mesoanalysis, which is a quite substantial indicator of tornado potential. A storm or two may approach western areas later this evening, but are expected to weaken as the move into the area in the 8-10pm timeframe. Most of our Nebraska counties should be storm-free by 8-9pm, but southern portions of the area have potential for a longer-duration event, with storms continuing to build near and just north of I-70. If this occurs, localized flooding is possible (mainly Mitchell/Osborne counties), although this will depend exactly on where storms setup. Monday will start off cloudy and relatively cool, with potentially some showers/drizzle in the morning and early afternoon. An additional round of convection is expected to develop along the stalled front. Less of the area is expected to be impacted than today and Saturday, but nevertheless, portions of northern KS, along with the Hwy 81 corridor could see severe storms in the 3-8pm timeframe. A Red Flag Warning remains in effect until 9pm today for southwestern zones that are expected to see a quick burst of dry air behind the dryline this afternoon. After today, the overall fire weather threat is relatively low for the rest of this week. Not much time was spent on the longer-range forecast. Temperatures remain below-normal through midweek, then gradually warm back up into the Memorial Day weekend. Rain/t-storm chances also return to the forecast by the end of next week. && .AVIATION /06Z TAFS THROUGH 06Z TUESDAY/... Issued at 1226 AM CDT Mon May 18 2026 For KGRI/KEAR Airports: At least Low-end MVFR ceilings are expected to dominate the 6z TAF period as a low deck of broken to overcast stratus remains lock in overhead. Ceiling will gradually lower through the night, reaching high end IFR levels just after sunrise (12-14z). KGRI may even drop into low-end IFR and LIFR between 16-20z. A period of drizzle to light rain is expected to impact both terminals between 14 and 19z. There is a low-end chance for a thunderstorm to be in the KGRI vicinity between 22-2z. Otherwise, winds will remain out of a northerly direction through the day (340-030 degrees) with speeds sustaining near 15-20kts and gusting as high as 25-35kts. && .GID WATCHES/WARNINGS/ADVISORIES... NE...None. KS...None. && $$ UPDATE...Stump DISCUSSION...Mangels AVIATION...Stump  266 FXUS63 KAPX 180738 AFDAPX Area Forecast Discussion National Weather Service Gaylord MI 338 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 /00Z TAFS THROUGH 00Z TUESDAY/... Issued at 1156 PM EDT Sun May 17 2026 Showers and a few embedded TSRA will tend to lift northward with time overnight. MBL/TVC/APN are done with the more widespread SHRA activity, but CIU/PLN are not. APN/CIU/PLN will both contend with IFR cigs at times overnight into Monday morning, ending from s to n. Conditions otherwise improve into Monday morning, until more showers/storms are possible in the afternoon and evening. Breezy southerly winds develop Monday. && .APX WATCHES/WARNINGS/ADVISORIES... MI...None. MARINE...Small Craft Advisory until 5 AM EDT early this morning for LHZ345-346. 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...JZ  383 FXUS66 KEKA 180741 AFDEKA AREA FORECAST DISCUSSION National Weather Service Eureka CA 1241 AM PDT Mon May 18 2026 .SYNOPSIS...Gusty north winds continue to ease today. Clear and dry conditions will remain through the week with a warming trend through Thursday. && .KEY MESSAGES... -Strong north winds will weaken today and through the week with only moderate north winds close to shore. -Generally clear skies and dry conditions, even along shore, through the week. -Conditions will warm through Thursday with highs in the interior peaking near 90. .DISCUSSION...Strong north winds continue to subside for Northwest California, especially near shore when compared to yesterday, but will persist through early today around the rim of the Sacramento Valley, especially Lake County. Strong mixing will continue to keep skies clear as temperatures begin to warm, especially across the interior. Wind overnight will continue to preclude any frost formation. High pressure will already begin to weaken but move more onshore today and through the week. This will lead to much weaker north winds with some moderate gusts to 20 mph still pushing in right along shore in the afternoon. Interior winds will transition to a more terrain controlled regime. Conditions will remain very dry with warming temperatures through the week. Highs will most likely top out around 90 for the interior on Thursday. This will constitute only a minor HeatRisk for this time of year. Hotter temperatures will help reform a marine inversion. Any stratus and fog; however, will most likely be very shallow and mix out quickly during the day. Compared to previous runs, most ensemble members continue to show a weak trough in the far extended forecast, but have it delayed until after next week. Rather most models show high pressure slowly weakening, allow temperature to drop, through next weekend. A trough early next week could bring some light showers or thunderstorms, but the vast majority of models currently remain dry. /JHW && .AVIATION...VFR conditions are expected for terminals in Northwest California as gusty north winds remain elevated, but quickly diminish early this morning. Winds will remain elevated for higher elevation areas of the Yolla Bollys and Lake County. Winds have diminished for more protected areas; however, winds remain elevated aloft, bringing LLWS concerns mostly for Mendocino County. && .MARINE...The pressure gradient relaxes slightly and the strongest winds move farther off the coast as the high pressure builds in. However, a large area of gale force gusts around 34-45 kts expected across all zones, with the strongest winds downwind of Cape Mendocino. Steep to very steep, hazardous seas will continue with the elevated winds. Conditions will remain hazardous across the waters for much of the workweek with strong to gale force gusts north winds and steep to very steep seas. Gale force winds and very steep seas are forecast to persists across the outer waters through Friday. /ZVS && .FIRE WEATHER...Strong north winds will continue, but diminish into the early morning. Winds will especially remain elevated around the rim of the Sacramento Valley and in Lake County today. Winds will weaken by this evening and transition to more gentle terrain wind through the week. Conditions will remain very dry with high temperatures increasing to near 90 for the interior by Thursday. && .EKA WATCHES/WARNINGS/ADVISORIES... CA... None. NORTHWEST CALIFORNIA COASTAL WATERS... Gale Warning until 3 AM PDT early this morning for PZZ450- 455. Gale Warning until 3 AM PDT Wednesday for PZZ470-475. && $$ NOTE: The full forecast discussion is now regularly issued between 10 am/pm and 1 pm/am. Additional updates will be issued as needed. Visit us at https://www.weather.gov/eureka Follow us on Facebook and Twitter at: https://www.facebook.com/NWSEureka https://www.twitter.com/NWSEureka For forecast zone information see the forecast zone map online: https://www.weather.gov/images/eka/zonemap.png  456 FXUS63 KGRB 180742 AFDGRB Area Forecast Discussion National Weather Service Green Bay WI 242 AM CDT Mon May 18 2026 Forecast discussion for routine morning forecast issuance .KEY MESSAGES... - Strong to severe storms and locally heavy rainfall possible at times through tonight. The greatest coverage of storms will occur across the northwest half of the forecast area early this morning, and again in the late evening and overnight hours tonight. - Drier and cooler weather returns mid to late week. Frost or freeze headlines may be needed over mainly northern WI Tuesday night and Wednesday night. && .DISCUSSION... Issued at 239 AM CDT Mon May 18 2026 A cluster of strong thunderstorms was ongoing over north central WI early this morning, in advance of a short-wave trough. This activity had marginal instability (MUCAPE 1000-1500) and strong deep layer shear (45-50 kts) to work with, and a few storms were pulsing to near-severe levels and exhibiting mid-level rotation at times. A marginal severe threat will continue over north central and perhaps far northeast WI through about 5 am. Otherwise, low clouds and areas of fog (locally dense) covered much of the region, and temperatures were stuck in the upper 40s to middle 50s. A warm front was situated across southern WI, where temperatures were in the lower to middle 70s. The warm front will lift north today, but there is some question if it will reach northern WI this afternoon. As the front lifts north and daytime heating commences, the foggy conditions should improve this morning. Have lowered max temperatures several degrees, especially over northern WI. Still expecting decreased coverage of storms today due to cloud cover, capping, a weakening low-level jet and weak mid to upper level ridging. Decreasing deep layer shear should also result in a lesser threat of severe storms during the day. Will keep slight chance to chance pops through the day and into the early evening hours. A surface wave will lift into north central WI later this evening, followed by a cold frontal passage during the overnight hours. CAMs show an uptick in thunderstorms over central and north central WI later in the evening, with a linear MCS moving through mainly north central and far northeast WI during the overnight hours. The late night timing of this is not especially favorable for severe storms, though MUCAPE of 1000-1500 j/kg and deep layer shear increasing to 35-50 kts supports severe potential. The cold front sweeps through eastern WI Tuesday morning with lingering showers and a few storms, but dry weather returns by afternoon. Tuesday will be a windy day with west to northwest winds gusting to 25 to 35 mph. Temps over eastern WI will remain above normal with highs in the low to mid 70s, but cooler readings in the 50s and 60s are expected farther west. High pressure will bring dry and cooler conditions for the middle of the week, with potential for frost or freeze headlines Tuesday night and Wednesday night. Warmer temperatures and small precipitation chances return for the weekend. && .AVIATION...for 06Z TAF Issuance Issued at 1238 AM CDT Mon May 18 2026 Scattered to widespread rain and thunderstorms are expected overnight as a line of convection moves in from the west. Isolated severe storms are possible in central and north-central WI within this line through ~09Z, with hail and wind gusts of 40 to 60 mph. However, the threat for severe storms at any one location is low. The more likely hazard is brief, heavy rain. Timed out best window for TSRA at each TAF site and included PROB30 groups. Meanwhile, mainly LIFR conditions are expected through the night due to low clouds and fog. Some improvement from south to north late tonight as a warm front lifts north. Thunderstorm potential should diminish by ~12Z Monday morning, with some lingering showers through mid-morning. Uncertainties arise after this, but the general consensus shows a cap in place for Monday which would limit any thunderstorm develop during the afternoon and evening, along with MVFR and VFR flying conditions. There is a greater threat for storms after 03Z/Tue as another line develops to the west and moves into the area. LLWS develops continues overnight and diminishes around 12-13Z. Easterly surface winds will veer to the south overnight, becoming southwest on Monday. Gusts up to 25 kts are possible at times. && .GRB WATCHES/WARNINGS/ADVISORIES... None. && $$ DISCUSSION.....Kieckbusch AVIATION.......KLJ  411 FXUS65 KFGZ 180742 AFDFGZ Area Forecast Discussion National Weather Service Flagstaff AZ 1242 AM MST Mon May 18 2026 .SYNOPSIS...Cooler and breezy conditions remain today behind a cold front. Gradually warmer and less windy conditions return for the remainder of the week. && .DISCUSSION...Today...Gusty winds remain over the higher terrain this morning as a cold front moves across northern Arizona. Winds should gradually subside from west to east with the frontal passage, thus for most of the area the Wind Advisory will expire by 5 AM MST / 6 AM MDT. Across eastern Arizona, FROPA looks to still be a couple hours later, so the advisory has been extended to 11 AM MST / 12 PM MDT. As the aforementioned front moves through the region, a brief period of showers will move from west to east, primarily near the AZ/UT border. Given that surface moisture will remain fairly minimal, much of the activity is expected to be either virga or light in nature. The best shot at measurable precip looks to mainly be across the Kaibab Plateau, an potentially Black Mesa and the Chuska Mountains as well. 00Z HREF guidance appears to be a bit bullish with precipitation chances, brining them as far south of as the Mogollon Rim. However, model soundings don't really support this outside of a subtle increase in low-level moisture early this morning. Nevertheless, PoP chances were maintained in the Flagstaff area for the potential for a couple isolated showers. Colder air aloft does move in with the front, so a few snow flakes may mix in at times above 7000-7500 feet. However any potential for measurable snow looks to remain above 7500-8000 feet and primarily near the Kaibab Plateau. Tuesday through Sunday...Zonal flow sets in behind the low earlier in the week. Warming temperatures and dry conditions look to ensue as a result, with a return to near-normal highs by the middle to end of next week. Weak troughing will keep winds fairly light each day, with mainly only the typical afternoon breezes expected. Ensemble guidance all signal towards PWATs increasing slightly by next weekend as a weak low looks to increase moisture advection into Arizona. For now, this looks to mainly result in a slight chance for some high-based showers around the White Mountains. && .AVIATION...Monday 18/06Z through Tuesday 19/06Z...Mainly VFR conditions. Brief periods of MVFR possible in -SHRA/-SHSN mainly north of a KGCN-KRQE line through 18Z. MVFR CIGS possible near KFLG/KSEZ 08Z-15Z. S-SW winds 15-30 kts with gusts 35-45 kts, subsiding to 10-20 kts after 08Z, then increasing to W-SW 10-20 kts with gusts 25-30 kts after 16Z. OUTLOOK...Tuesday 19/06Z through Thursday 21/06Z...Mainly VFR conditions. Variable winds 5-15 kts on Tuesday, then SW-NW 5-15 kts on Wednesday. && .FIRE WEATHER...Today and Tuesday...Slight chance for light showers and possibly a thunderstorm this morning across far northern Arizona, otherwise dry and cool conditions. Winds west/southwest 10- 20 mph with gusts 25-35 mph, subsiding to 5-15 mph on Tuesday. Minimum afternoon RH 10-30%, falling to 10-20% on Tuesday. Wednesday through Friday....Dry conditions with gradually warming temperatures. Winds west/southwest 5-15 mph each day, along with minimum afternoon RH 5-15%. && .FGZ WATCHES/WARNINGS/ADVISORIES... Wind Advisory until 5 AM MST /6 AM MDT/ early this morning for AZZ004-006-009-012-013-015-016-039-040. Wind Advisory until 11 AM MST /noon MDT/ this morning for AZZ011- 014-017. && $$ PUBLIC...Humphreys AVIATION...Meola FIRE WEATHER...Humphreys For Northern Arizona weather information visit weather.gov/flagstaff  455 FXUS65 KMSO 180742 AFDMSO Area Forecast Discussion National Weather Service Missoula MT 142 AM MDT Mon May 18 2026 .DISCUSSION... KEY MESSAGES: - Frost/freeze concerns remain Tuesday mornings. - Northwest flow becomes established for the rest of the week with unsettled but mild conditions. Clear skies are allowing temperatures to drop overnight, expect widespread temperatures in the 20s and low 30s this morning and while there will be moderation Tuesday expect another cold start. For the kids, a jacket in the morning will be carried home during the afternoon. Its vulnerable vegetation that will need care the next 2 mornings. Afternoon heating today and potentially again tomorrow will allow for isolated showers, production of graupel, and potentially a lightning strike or two. We will remain in northwest flow with a high pressure ridge just off the west coast. In the simplest terms, this week will see a warming trend and by Friday temperatures will be a few degrees above normal. A few disturbances will slide south along the eastern part of ridge producing periods of showers. Currently, the models are not overly excited, however, Wednesday evening into Thursday could be a period of more organized shower activity, especially along the continental Divide. && .AVIATION...Cold mornings may allow for fog in the vicinity of terminals, especially KBTM and KGPI. Otherwise, the atmosphere will remain unstable but dry, showers may develop in the vicinity of KGPI between 18/2100 and 19/0000z. Thunderstorms are very low probability, 20% or less, however a lightning strike is possible in the Flathead Valley and surrounding mountains. && .MSO WATCHES/WARNINGS/ADVISORIES... MT...Frost Advisory until 8 AM MDT this morning for Kootenai/Cabinet Region...Lower Clark Fork Region. Frost Advisory until 9 AM MDT this morning for Flathead/Mission Valleys...Missoula/Bitterroot Valleys. ID...None. && $$  862 FXUS61 KCTP 180746 AFDCTP Area Forecast Discussion National Weather Service State College PA 346 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 /07Z MONDAY THROUGH FRIDAY/... Patchy fog remains a low (<30%), but nonzero, possibility tonight with light winds and mainly clear skies. Localized visibility drops have been observed (e.g. KMUI in Lebanon County briefly dropping to 2.75 miles at 00:35Z Monday), though model guidance has trended toward less numerous mist/fog across the region. For this reason, we've maintained no mentions of visibility restrictions to our TAF sites. Otherwise, regionwide VFR is expected through Monday afternoon. Regarding the chance for convection Monday afternoon: 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 92 in 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/Lambrech CLIMATE...Dangelo/Steinbugl  954 FXUS65 KVEF 180748 AFDVEF Area Forecast Discussion National Weather Service Las Vegas NV 1248 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 06Z Forecast Package...Gusty south to southwest winds will continue through the morning hours gusts of 30 to 40 knots likely. Winds will gradually diminish through the morning. Periods of low-level turbulence can be expected through the midday Monday. No significant ceilings or visibility concerns are expected through the TAF period For the rest of southern Nevada, northwest Arizona and southeast California...For the 06Z Forecast Package...Strong winds will continue across much of the region through the morning Monday at Las Vegas Valley TAF sites, while strong winds gusting to 30+KT will persist through the day in the Colorado River Valley. No significant ceilings or visibility concerns are expected through the TAF period. && .SPOTTER INFORMATION STATEMENT...Spotters are encouraged to report any significant weather or impacts according to standard operating procedures. && $$ DISCUSSION...Meltzer AVIATION...Planz For more forecast information...see us on our webpage: https://weather.gov/lasvegas or follow us on Facebook and Twitter  933 FXUS66 KOTX 180748 AFDOTX Area Forecast Discussion National Weather Service Spokane WA 1248 AM PDT Mon May 18 2026 .KEY MESSAGES... - Pop up showers and isolated thunderstorms primarily over the higher terrain will return Monday afternoon. - Cold overnight temperatures will bring a threat of morning frost Monday. This could impact sensitive plants or crops. - Conditions trend drier and warmer through the workweek regionwide, with periodic breezy winds for the Cascades and central WA. && .SYNOPSIS... Diurnally forced showers with isolated afternoon thunderstorms will continue today Monday. Precipitation chances decrease and afternoon highs trend warmer through the workweek, climbing back into the 70s and 80s by Thursday and continuing through next weekend. Breezy winds are expected at times through the Cascade gaps and across the western Columbia Basin. && .DISCUSSION... Today through Friday night: A deep longwave trough of lower pressure will remain over the CONUS for this weekend through the workweek. The axis of this longwave trough will slowly migrate over the Rockies by through Wednesday and then over the Plains by Thursday into Friday. The Inland Northwest will remain under the backside of this trough today with a conditionally unstable air mass. Lingering showers over extreme eastern Washington into the Idaho Panhandle early this morning will wane with decreasing instability at mid levels. However, diurnal heating will destabilize the lower levels of the atmosphere for the afternoon. There will be a lack of instability over the Columbia Basin today, which should result in much of the showers and thunderstorm activity confined to mainly the higher terrain today. Instability parameters will be much less compared to Sunday with upper levels trending warmer. Much less likely to see as much small hail like we've seen with this storms, but some is expected with slightly stronger thunderstorms over the mountains. Convection will also be capable of wind gusts up to around 20-25 mph and infrequent cloud to ground lightning strikes. Best potential for thunderstorms today will be over northeast Washington into the Northern Panhandle with 20-25% chance of occurring. Convection is expected to wane more quickly into the evening hours compared to Sunday. We then see a drying trend into mid week as a ridge of higher pressure in the eastern Pacific nudes east into the Northwest. There is a shortwave disturbance that pushes across BC on Tuesday and does bring a 20-30 percent chance for showers across the far northern mountains closer to the Canadian border, and this potential could linger into Wednesday for North Idaho as the shortwave pushes across fairly slowly. There is a 15% chance that places like Lauier, Northport, Metalline Falls, Porthill, and Eastport may also see a passing thunderstorm. Temperatures warm up above normal by Wednesday with our highs back into the 70s. The risk for morning frost will decrease as well as temperatures see a slow warm into the weekend. Saturday through Sunday: Model ensembles remain in pretty good agreement with a shortwave trough of lower pressure to flatten the ridge. There is uncertainty with how deep this shortwave will be. About 80 percent of the ensemble members show this disturbance to be fairly weak with minimal cooling of just a few degrees Saturday into Sunday. Westerly winds will see an increase. Stronger wind gusts of up to around 30 mph will be across the Cascades and into the western basin and up to around 20-25 mph potentially into places like Spokane and the Palouse. Winds would pick up Saturday afternoon, but could also remain fairly breezy into Sunday as well. Models continue to diverge as we head into the beginning of next week. Outliers such as the 00Z operational ECMWF and Canadian indicate a deep trough to dig in into BC and potentially as far south as the Pacific Northwest. This scenario would represent more cooling and a better potential for showers than what is in the forecast. The NBM suggests a more zonal flow pattern with the potential for progressive weaker waves that could bring light shower activity but nothing looking all that substantial. After our warm up late in the week, temperatures look to cool near normal for Sunday into the beginning of next week. /SVH && .AVIATION... 06Z TAFs: Showers lingering along an axis of elevated instability near the Washington/Idaho border with showers expected to wane over the next few hours (by 10Z). The boundary layer is fairly moist now in extreme eastern Washington into the Idaho Panhandle. This will increase the potential for fog and low stratus to develop. How much fog develops will largely depend on how quickly the mid level cloud cover dissipates overnight with the waning showers. Expecting at least patchy fog for KGEG/KSFF/KCOE and areas or fog to develop in the northern mountain valleys around Colville (K63S), Deer Park (KDEW) and Sandpoint (KSZT). Low stratus or stratocumulus deck with MVFR ceilings is expected at KPUW for Monday morning. A redevelopment of convective showers with isolated thunderstorms is expected with diurnal heating on Monday over the mountains of northeast Washington into the Idaho Panhandle. FORECAST CONFIDENCE AND/OR ALTERNATE SCENARIOS: Confidence is low for visibility restrictions and IFR conditions with radiational fog at KGEG/KSFF/KCOE for Monday morning. Moderate to high confidence for low ceilings and MVFR conditions with stratus or stratocumulus that also includes KPUW. /SVH ----------------------- Confidence descriptors: Low - Less than a 30 percent chance Moderate - 30 to 70 percent chance High - Greater than a 70 percent chance For additional probabilistic information for NWS Spokane airports, please refer to the Aviation Dashboard on our webpage: https:/www.weather.gov/otx/avndashboard && .Preliminary Point Temps/PoPs... Spokane 66 41 69 44 72 45 / 10 10 0 0 0 0 Coeur d'Alene 64 41 67 44 70 45 / 20 20 10 0 0 0 Pullman 62 39 65 42 68 43 / 10 0 0 0 0 0 Lewiston 67 43 71 46 73 48 / 10 0 0 0 0 0 Colville 69 36 71 40 75 41 / 20 30 10 10 0 0 Sandpoint 62 40 66 43 68 43 / 30 30 10 10 0 0 Kellogg 61 39 66 43 68 43 / 20 20 10 0 10 10 Moses Lake 73 42 75 46 78 49 / 0 0 0 0 0 0 Wenatchee 72 48 74 51 77 54 / 10 0 0 0 0 0 Omak 73 43 75 48 78 51 / 10 10 10 0 0 0 && .OTX WATCHES/WARNINGS/ADVISORIES... WA...Frost Advisory until 7 AM PDT this morning for Northeast Mountains-Okanogan Highlands-Spokane Area-Washington Palouse. ID...Frost Advisory until 7 AM PDT this morning for Central Panhandle Mountains-Coeur d'Alene Area-Idaho Palouse- Northern Panhandle. && $$  305 FXUS61 KCAR 180757 AFDCAR Area Forecast Discussion National Weather Service Caribou ME 357 AM EDT Mon May 18 2026 .WHAT HAS CHANGED... -Continued to lower dewpoints for today -Made a general area of thunder on Tuesday. Confidence in some storm development on Tuesday increases. -Added thunderstorm potential for Downeast areas Wednesday -Added key message for frost/freeze potential early Friday morning and below average temperatures -Removed key message for rain Sunday as chances have decreased and the overall impact is low if it occurs && .KEY MESSAGES... 1) Dry and breezy conditions today, potentially leading to some fire weather concerns. 2) Chance for thunderstorms and warm temperatures Tuesday and Wednesday afternoon. A few stronger storms are possible. 3) Below average temperatures are expected Thursday and Thursday Night. Near freezing temperatures are possible early Friday morning across the north, which may require actions to protect vulnerable plants. && .DISCUSSION... KEY MESSAGE 1...Dry and breezy conditions today, potentially leading to some fire concerns. KEY MESSAGE 1 DESCRIPTION... Period of high pressure today, as a warm front slowly begins to approach from the southwest. Front to the southwest brings in a few clouds, helping to keep daytime high temperatures around the mid-60s in northern and eastern Maine. Very dry mid-level moisture based on sounding analysis, with daytime minimum RHs expected to be upper 20s/low 30s in the northwest, and low 20s in northern and eastern Maine. Winds shift to the southwest, with some breezy conditions during the early evening, predominantly Downeast. KEY MESSAGE 2...Chance for thunderstorms and warm temperatures Tuesday and Wednesday afternoon. A few stronger storms are possible. KEY MESSAGE 2 DESCRIPTION... Ridging over the central Atlantic moves east Monday night, as a low pressure system and associated warm front moves into the region by Tuesday morning. A mid-level shortwave moves through during the afternoon into the evening. The region warms up as a warm front passes, raising daytime highs to roughly low-70s up north, low-80s in the Central Highlands, and mid-80s in the Bangor and Downeast region. Current uncertainty resides in the timing of the frontal system, as this will heavily impact daytime temperatures and precipitation timing. Instability rises during the afternoon, bringing with it the chance for some thunderstorms across the Central Highlands, Bangor to Downeast region. On Tuesday, potential for roughly 1500 J/kg of CAPE, decent shear parameters, and PWATs roughly around 1.25 - 1.75 inches. The main threat with these storms seems to be severe wind gusts, as low-level lapse rates are close to 7 - 7.5C/km, and DCAPE is around 600-800 J/kg. There is also a chance for some hail to fall from some of these storms. Make sure to have access to ways for receiving warning alerts if a storm develops in your area. Thunderstorm potential will begin to dissipate by nighttime. By Wednesday a strong cold front will approach the area, accompanied by much drier air at all levels behind it. Models differ significantly with the timing of the front, with the NAM and GFS on the faster and the CMC/ICON/ECMWF on the slower end. A faster solution would result in little to no convection as deeper moisture is forced over the ocean where conditions are extremely stable. Slower solutions would result in a narrow band of 500-1000 J/kg of MLCAPE across Bangor into Downeast Maine, which combined with stronger winds aloft providing 30-40 kts of 0-3km effective wind shear, could lead to an isolated thunderstorm capable of strong to damaging winds for coastal and Downeast areas. A majority of the time, slower solutions for frontal passages verify this time of year, so adjustments were made to expand PoPs and introduce thunder chances mainly Downeast and over the near coastal waters. The speed of the front will also impact temperatures, with slower solutions potentially allowing 80s to reach farther to the north. Max temperatures mainly in the 70s are forecast for northwestern with 80s most likely near and southeast of interstate 95. Dew points in the 60s early will make it feel a somewhat humid, but drier air and much lower dew points will quickly move in behind the front in the afternoon from northwest to southeast. KEY MESSAGE 3...Below average temperatures are expected Thursday and Thursday Night. Near freezing temperatures are possible early Friday morning across the north, which may require actions to protect vulnerable plants. KEY MESSAGE 3 DESCRIPTION... The frost/freeze program, marking the approximate beginning of the growing season, will expand north on Thursday to include most of the remainder of northern and eastern Maine aside from the far northwestern forecast zones. Strong cold air advection is expected on Thursday with 1000-500mb thicknesses decreasing below 540dam across much of northern Maine by Thursday evening. While winds will be lighter Thursday night, the center of the ridge of high pressure is expected to be well to the southwest across northern NY, VT, and western MA, helping to maintain a modest NW wind outside of sheltered valleys. A strong jet streak overhead will also maintain the risk for passing clouds. These factors make the actual degree of decoupling uncertain. Temperatures at or below freezing are most likely over the North Woods where the growing season does not start until June 1. Lows ranging from the mid 30s to lower 40s are favored elsewhere early Friday morning. && .AVIATION /07Z MONDAY THROUGH FRIDAY/... Today...VFR. Winds shift from NW to W by later in the morning. Gusts up to 20 kts possible around KBGR. Tonight...VFR/MVFR, with some rain showers at northern terminals. S winds at 5 - 10 mph. LLWS possible. Tuesday...MVFR, potentially lower in terminals with severe thunderstorms. Best chance for thunderstorms is during the afternoon into evening. WSW winds G15-20KT possible Tuesday afternoon. LLWS possible. Tuesday night: MVFR possible at northern terminals, IFR possible at KFVE. VFR elsewhere. SW winds 5 to 10 kts gusting to 20 kts. Wednesday: MVFR early at northern terminals, otherwise VFR. Tempo MVFR/IFR is possible at BGR and Downeast terminals with a chance of a TSRA. Windy with WSW winds turning WNW at 15 to 20 kts with gusts to 30 to 35 kts. Wednesday night to Thursday: VFR. NW winds 10 to 15 kts with gusts to 25 to 30 kts. Thursday night: VFR. NW winds 5 to 10 kts. Friday: VFR. NW winds 10 to 15 kts gusting to 20 to 30 kts. && .MARINE... Winds stay below SCA Monday night, before creeping near marginal Small Craft criteria for the outer waters Tuesday. Chance for rain Monday night and Tuesday. S winds, becoming SW on Tuesday. Marginal Small Craft Advisory seas around 4 to 6 feet are possible over the outer waters out to 25NM Tuesday night through Wednesday evening. Wave heights to around 5 to 7 feet are possible across the outermost waters from 25 to 60NM. Winds below advisory levels are expected through the forecast period, although some 25 kt gusts are possible across the outermost waters from 25 to 60NM offshore Tuesday night into Wednesday. An isolated thunderstorm is possible Wednesday afternoon, mainly closer to the coast. These thunderstorms may produce locally stronger wind gusts. Sea surface temperatures remain very cold, but are beginning to moderate into the mid 40s. && .CAR WATCHES/WARNINGS/ADVISORIES... ME...None. MARINE...None. && $$ DISCUSSION...ASB/MWS AVIATION...ASB/MWS  332 FXUS61 KPHI 180757 AFDPHI Area Forecast Discussion National Weather Service Mount Holly NJ 357 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 /06Z MONDAY THROUGH FRIDAY/... The following discussion is for KPHL, KPNE, KTTN, KABE, KRDG, KILG, KMIV, KACY and surrounding areas. Through 12Z...VFR. Winds mostly calm, if not SSW less than 5 kts. High confidence. 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 dangerousand 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 Site Record/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