012 FXAK67 PAJK 220000 AFDAJK Southeast Alaska Forecast Discussion National Weather Service Juneau AK 400 PM AKDT Fri Aug 21 2026 .SYNOPSIS... Key Messages: - An active weather pattern will continue through the weekend with mostly cloudy skies and periods of rain, with chances increasing into Sunday for the southern panhandle. - Winds are likely to be variable with frontal passages, and at times gusty, especially within the northern inner channels as afternoon sea breezes develop. && .SHORT TERM.../through Sunday night/... Rain is expected to continue through Friday afternoon and evening in the northmen panhandle with the heaviest rainfall expected from 4pm to 10pm. Mean values from the NBM are projecting 0.9 inches in Juneau all the way down to 0.5 inches around the rest of the northern panhandle. After this period of heavier rain across the north, the stream of moisture begins falling southeast across the panhandle. Rain in the northern panhandle looks to fall off between 1am and 4am Saturday, which is around when it will start raining in the southern panhandle. The front is likely to bring showers to Petersburg, Wrangell, and Prince of Wales Island, but precipitation chances in Ketchikan and Annette Island remain low. Rain looks to move mostly out of the area by 10am Saturday due to an area of high pressure building over the panhandle followed by a dry slot. The highest chance for rain on Saturday sits around 30-40%, but skies are likely to remain cloudy across the panhandle. Rain chances then increase across the panhandle Saturday night into Sunday morning across the panhandle as a low pressure system in the gulf meets with the moisture transport from lower latitudes. This is likely to bring heavy, widespread rain across the panhandle through the day Sunday. Current thinking is that the northern panhandle will see greater accumulations in the morning and the southern panhandle will see greater accumulations Sunday night. 850mb temperatures are expected to remain slightly more elevated through the day Saturday, bringing high 60s to the southern panhandle, but the next system will wipe out warm temperatures. on Sunday, high 50s and low 60s can be expected across the area. .LONG TERM.../Monday through Thursday/...The low pressure system bringing widespread rainfall to the panhandle Sunday will continue to shift southeastward through Monday, moving out of the northern panhandle and lingering over the southern and parts of the central panhandle through the day. The models have come more in line on the low positioning, indicating that the southern panhandle will see the highest rainfall amounts with this system. As the low moves in from the west, the northern panhandle should see the front move in first before rainfall quickly spreads to the rest of the panhandle through Sunday morning. Most of this rain will fall overnight into early Monday morning, tapering off from northwest to southeast through Monday evening. Expecting around an inch and a half of rainfall for parts of the southern panhandle in 24 hours from early Monday morning through early Tuesday morning. Light winds are expected for a majority of the panhandle behind the front, though sea breezes are expected to increase through some of the inner channels Tuesday afternoon, particularly in Lynn Canal. Potential for a break continues to increase for the early week as the low dips south, though keeping an eye on upper level easterly flow that may allow for showers in BC to traverse into the panhandle. The northern and central panhandle have potential to see some sun behind this front on Monday, with the southern panhandle joining in by Tuesday. The slight period of ridging that develops over the eastern gulf should allow winds in the inner channels to switch to a more offshore direction overnight before the weather becomes more active through the second half of the week. With the potential for clearing, sea breezes should increase through midday and turn winds back onshore for a period. Daytime high temperatures will also increase above normal for days that see this clearing, allowing for highs reaching the high 60s to low 70s across the panhandle Tuesday. The next system is expected to reach the panhandle through Wednesday. NBM PoP is getting washed out through the end of the week, so slightly increased confidence through the northern panhandle with the onset of the front. && .AVIATION.../through 00Z Sunday/...The front continues to impact the northern panhandle and outer coastline through this afternoon and evening, with precipitation expected to increase over the central region near PAPG and PAWG overnight. On the other hand, the southern panhandle currently experiencing clear skies will gradually transition to overcast conditions as a surface low pushes southward. A temporary break in cloud cover is expected for the northern panhandle tomorrow morning between 12Z and 18Z, likely resulting in VFR conditions. However, low clouds and fog may persist due to recent rainfall and a surface inversion maintaining moisture below 5000 ft. In the southern panhandle, a band of rain is forecasted to pass over Prince of Wales and Wrangell Island between 09Z and 15Z, with minimal impacts further southeast, though PAKT may experience MVFR CIGs during this time. Winds are expected to remain mostly calm overnight, with peak speeds of 10 to 15 knots isolated to sites near Lynn Canal, including PAGY, PAHN, and PAJN. While turbulence impacts are expected to lessen, wind direction will remain variable with the frontal passage through the Icy Strait Corridor and as far south as Frederick Sound. Finally, a continued push of tropical moisture keeps a warming trend for freezing levels, which are currently situated between FL100 and FL120. && .MARINE... Outside: Lots to write about, the simple message is westerly moderate breezes fill in across the Gulf tonight, with fresh breezes near Cape Spencer and Dixon. Mariners moving in and out of Cross Sound should be aware of westerly fresh seas and the tide timings. There still exists high uncertainty with a system moving into the Gulf Sunday. For Sunday, current forecast shows confidence in ESE moderate breezes along our coast; however, we could see more extensive fresh breezes across coastal waters. Current SITREP along our northern coast is clean SSW swell 14 seconds near 3 to 4 ft, with diminishing seas 8 seconds 4 to 5 ft from Cross Sound to Cape Decision. Winds are becoming westerly at gentle to moderate breezes. However, Cape Spencer and Dixon Entrance will see fresh breezes into Saturday. Primary impact is for folks on small skiffs moving around. Saturday a system will begin to move off the Alaska Peninsula, driving a fetch of southwest strong breezes across the western Gulf. The primary question is how strong will winds become along our coast as this system moves east, with a variety of solutions. Some high res guidance wants to put 20 knots of SE winds along our coast by Sunday afternoon, while others suggest winds at a respectable 10 to 15 knots. For now, we highlight moderate breezes for most of our coast. Either way, this feature will start to bury the low amplitude 12 to 14 seconds SSW swell, becoming seas focused near 8 seconds 4 to 5 ft for Sunday. If we see 20 knots of winds, SE seas of 5 to 7 ft become more likely along the northern coast, primarily impacting folks in smaller recreational fishing vessels. Inside: A slightly stronger than anticipated front is moving across the Panhandle this afternoon, freshening winds up across Chatham and Stephens to moderate breezes. Anticipate these southerly winds to move up Chatham this evening into Glacier Bay and portions of Icy. While not the blow of the century, a 15 knot wind in a long fetch can make crossing major passages in a small skiff uncomfortable. Further north in Lynn Canal, strong breezes (22 to 27 knots) were reported earlier, which have diminished to fresh breezes. For northern Lynn, expect this short break to continue this afternoon but late Friday to early Saturday southerly winds will increase back to strong breezes, perhaps near-gale force, persisting into Saturday evening. Furthermore, Friday night into Saturday anticipate westerly winds of moderate to fresh breezes (15 to 21 knots) to build across western Icy Strait, likely moving up into the lower Glacier Bay. This could complicate vessels planning to transit Bartlett Cove. Winds slowly diminish Saturday afternoon with the exception of northern Lynn Canal. && .AJK WATCHES/WARNINGS/ADVISORIES... PUBLIC...None. MARINE...Small Craft Advisory for PKZ012. && $$ SHORT TERM...AGP LONG TERM...ZTK AVIATION...BAS MARINE...AP Visit us at http://www.weather.gov/Juneau  100 FXUS61 KCAR 220001 AFDCAR Area Forecast Discussion National Weather Service Caribou ME 801 PM EDT Fri Aug 21 2026 .WHAT HAS CHANGED... Updated Aviation section for 00z TAFs && .KEY MESSAGES... 1) There is the potential for widespread rainfall from Sunday into Monday. It is not certain how much, if any, relief this could bring to the ongoing drought at this time. && .DISCUSSION... KEY MESSAGE 1...There is the potential for widespread rainfall from Sunday into Monday. It is not certain how much, if any, relief this could bring to the ongoing drought at this time. KEY MESSAGE 1 DESCRIPTION... A closed low pressure system developing over the Mid Atlantic coast will progress north on Saturday and move rain into the region Saturday night. The CAMs are starting to grab onto the storm giving a clearer picture of the rain timeline. Expect rain to begin along the coast Saturday evening and push NNE through Saturday night. The question for Saturday night will be how much rainfall will occur, especially for areas in the north. Unfortunately, the ensembles still disagree on amounts as of this update. After midnight, the center of the low will be over Downeast. As this coastal low moves northward, a vertically stacked low pressure system centered over the Great Lakes will progress E over New England. This new low is expected to weaken the coastal low, which will increase the amount of moisture within the stronger low. By Sunday, expect widespread rainfall continuing throughout the day. Throughout Sunday night, the low becomes stationary over Quebec as it rotates the moisture through the state. By Monday, the low begins to gradually move north which will decrease rain chances throughout the day. Since the rain amounts are unknown as of this update, it is unknown if this system will bring any relief to the ongoing drought. && .AVIATION /00Z SATURDAY THROUGH WEDNESDAY/... High confidence in VFR through the TAF period from KHUL on north. High in VFR at KBGR through 18Z Saturday, with gradually increasing chances of MVFR 19-24Z (but still too low to reflect in the TAFs at this time). High confidence in VFR at KBHB through midday Saturday. MVFR develops there during the early afternoon hours. There is a low chance of IFR at KBHB by the end of the TAF period, however there is not sufficient confidence to place in the TAFs at this time. Winds become light and variable throughout early this evening. SE winds at 6-10KT develop at northern terminals around midday, then become light and variable at all but KFVE early Saturday evening. At southern terminals, a NE wind at around 10KT develops by mid Saturday morning. Saturday night: Becoming IFR or lower at all terminals in rain. E-SE winds G15-20KT possible. Sunday-Monday: IFR or lower likely. Slight chance for thunderstorms Sunday night and again Monday afternoon. S-SW winds G15-20KT possible Monday. Monday night-Wednesday: MVFR or lower likely at northern terminals. MVFR possible at KBGR, with VFR likely at KBHB. LLWS possible Monday night. W-NW winds G15-20KT possible Wednesday. && .MARINE... Winds generally below 20 kt through Saturday night, though east winds approach 25 kt over 25-60NM waters Saturday afternoon/evening. Seas build to 2-4 ft with highest seas over the waters from 25-60nm Saturday evening. Patchy fog and rain may reduce visibilities to 1-3NM. Slight chance of winds or seas reaching 25 kts/5 ft Monday- Tuesday. Fog likely the next few nights. A chance for thunderstorms on Sunday and Monday. && .CAR WATCHES/WARNINGS/ADVISORIES... ME...None. MARINE...None. && $$ DISCUSSION...ARL/PM AVIATION...21/ARL/PM  113 FXUS64 KMOB 220001 AFDMOB Area Forecast Discussion National Weather Service Mobile AL 701 PM CDT Fri Aug 21 2026 ...New AVIATION... .KEY MESSAGES... Updated at 700 PM CDT Fri Aug 21 2026 - Very hot conditions continue today with peak heat indices in the 108 to 112 range. - Scattered to numerous thunderstorms this afternoon will continue to be capable of producing brief intense rainfall, excessive lightning, and strong to damaging wind gusts. && .UPDATE/DISCUSSION... Issued at 525 PM CDT Fri Aug 21 2026 Ongoing this afternoon, keeping a close eye on convection ongoing generally along and north of the I-10 corridor. Plenty of support in place for strong to severe thunderstorms, including ample dry air entrainment per recent GOES-16 Precipitable water, resulting in extremely high DCAPE across central MS/AL and plenty of available instability. Environmental favorability for severe weather is in place, but focus will be on any outflow boundary and/or seabreeze interactions to individual, pulse-like severe storms causing damaging downburst winds. REFS guidance/trends slides all convection south late this afternoon/evening, but not entirely sure this will happen as they interact with the post- seabreeze environment along the coast, with low confidence on this activity sagging south through the evening. If it does, the severe threat will transition into coastal marine areas around sunset with ongoing gusty winds the main risks. Drier air filters into the area tomorrow through Sunday, resulting in lower forecast PoPs and greater PBL mixing to cause a reduction in the heat risk. Not anticipating the need for an advisory tomorrow as heat indices range in the 103-106 range, still hot though. Could still see an isolated storm along the seabreeze, but keeping PoPs in the 10-20% range both Saturday and Sunday afternoons. Monday into next week, focus shifts to the northwest as we could likely see distinct PVA/impulses riding around the periphery of the ridge across the four corners region. This could introduce a series of long-distant MCS's from the central MS valley region into the northern Gulf coast. Something we'll need to carefully monitor for Monday and Tuesday. Mid to late week, we return right back to the typical summertime pattern but again with ongoing impulses from the north. Afternoon heat indices remain below criteria/heat risk impacts remain limited throughout the week with highs in the low 90's, but PoPs remain elevated with daily localized strong to isolated severe storm risks. KLG && .AVIATION... (00Z TAFS) Issued at 700 PM CDT Fri Aug 21 2026 Scattered showers and storms are expected through early to mid evening across portions of the area. A few of the TAF sites may experience brief drops to MVFR or lower conditions and gusty winds with this activity through around 01-02Z, though isolated strong to severe storms may persist a bit longer over the interior. Additional showers and storms cannot be ruled out along the immediate coast late tonight into early Saturday. Otherwise, VFR conditions are expected to prevail through the period. Light northerly flow is expected for Saturday, turning more southerly or southwesterly along the coast at around 8-12 knots in the afternoon. JGC/98 && .MARINE... Issued at 325 AM CDT Fri Aug 21 2026 No impacts expected other than locally higher winds and seas possible near thunderstorms. /13 && .PRELIMINARY POINT TEMPS/POPS... Mobile 74 95 74 96 / 30 10 0 20 Pensacola 78 93 78 95 / 20 20 0 20 Destin 79 91 79 93 / 40 20 10 10 Evergreen 71 97 71 98 / 40 10 0 10 Waynesboro 72 99 73 100 / 30 0 0 0 Camden 72 97 72 96 / 20 0 0 10 Crestview 73 96 72 97 / 30 20 10 20 && .MOB WATCHES/WARNINGS/ADVISORIES... AL...Heat Advisory until 8 PM CDT this evening for ALZ051>060-261>266. FL...Heat Advisory until 8 PM CDT this evening for FLZ201>206. MS...Heat Advisory until 8 PM CDT this evening for MSZ067-075-076-078- 079. GM...None. && $$  214 FXUS66 KOTX 220003 AFDOTX Area Forecast Discussion National Weather Service Spokane WA 503 PM PDT Fri Aug 21 2026 .KEY MESSAGES... - A Heat Advisory has been issued through Friday evening due to very warm temperatures and widespread Major HeatRisk. - Saturday system brings increased chances for showers, thunderstorms, and gusty winds. This will lead to critical fire weather conditions across the Inland Northwest. - Patchy blowing dust is possible Saturday in the Western Columbia Basin. && .SYNOPSIS... Temperatures will be very warm Friday with widespread Major HeatRisk. A pattern change Friday night into Saturday will bring unsettled conditions with chances for showers, thunderstorms, and gusty winds. Sunday will remain breezy and dry, but cooler. Temperatures will warm again at the start of next week with breezy conditions returning by the middle of next week. && .DISCUSSION... Friday through Sunday: An incoming cold front will bring gusty winds and isolated to scattered thunderstorms to the region Saturday into Sunday. Today, ahead of the cold front passage on Saturday, temperatures have warmed into the high 90s with triple digits possible in the lower Basin. This has led to widespread Major HeatRisk values, so anyone without adequate cooling and hydration as well as health systems and industries could see impacts. A Heat Advisory is valid through much of the Inland Northwest through 10 PM this evening and low temperatures into tomorrow will be in the 60s and 70s and provide little overnight relief. Tonight into Saturday, moisture advection ahead of the frontal passage will raise PWATs to 125 to 150 percent of normal, around 0.75 to 1 inch. The arrival of the cold front on Saturday accompanied by a 40-50kt 500mb jet and warm overnight and daytime temperatures will create a favorable environment for isolated to scattered thunderstorms across the Cascades and northern mountains. While these showers will initially start out as isolated in nature, as daytime warming increases, thunderstorms become more scattered in nature, especially into Saturday afternoon and evening. With PWATs near 1 inch and DCAPE values 500 J/kg and higher, main impacts look to be isolated heavy rainfall rates, gusty outflow winds up to 50 mph, and lightning induced fire starts. Steep terrain and burn scars will need to be monitored for any heavy rainfall rates. This threat will move eastward across the forecast area through the day, and Saturday night into Sunday morning the ID Panhandle sees isolated to scattered thunderstorms. To reflect these critical fire weather conditions, Red Flag Warnings have been issued. For the Cascades and northern mountains, the Red Flag Warning is valid from Saturday morning through Sunday morning. For the ID Panhandle, the Red Flag Warning is valid from Saturday afternoon through Sunday morning. Another impact from this cold front will be gusty winds leading to critical fire weather concerns across the Basin and Spokane area. There is a 40 percent chance and higher for most locations in the region to see wind gusts higher than 30 mph on Saturday night. Areas that will see the highest gusts include the Lewiston, Moses Lake, Wenatchee, and Waterville Plateau areas. A Red Flag Warning for the basin, Palouse, and Spokane areas is valid from Saturday afternoon through Saturday evening. Potential impacts from these winds include rapid spreading of wildfires alongside blowing objects and difficulties driving, especially for high profile vehicles. While models initially had the low moving out of the area quicker, there is now better agreement that the low lingers over the state of Washington through Sunday before moving out of the area Sunday night into Monday. Impacts will continue to be seen into Sunday afternoon with residual winds and isolated to scattered thunderstorms in the northern Idaho Panhandle. One thing to keep a close eye on is the extent of the thunderstorms post cold frontal passage on Sunday morning. As high-res models pick up the end of the event Sunday morning, they are showing enough lingering instability throughout fire zone 708 (Eastern Columbia Basin/Palouse/Spokane area) that it may need to be added into the Red Flag Warning. Wind gusts around 15- 20 mph will linger throughout the Cascade gaps, Okanogan Valley, Waterville Plateau, Columbia Basin, Spokane/CdA, and Palouse areas through late Sunday afternoon, bringing continued elevated fire weather conditions. A significant cooldown due to the cold front will be observed Saturday into Sunday, with high temperatures dropping around ten or more degrees. Temperatures will end up being a couple degrees below normal on Sunday. Apart from the northern mountains and Cascades, precipitation chances drop down to near zero. Monday through Wednesday: With high confidence (80 percent of clusters) indicating a strengthening ridge building over the area early next week, the temperature drop will be short lived. By Tuesday, temperatures will again warm into the high 80s to low 90s. Clusters show a 50 percent chance of another trough approaching the PNW coast, though timing and track are uncertain. This could lead to a return of gusty winds and thunderstorm chances. Overall chances for precipitation remain low, with PoPs 15 percent and lower expected Monday through Wednesday. /AS && .AVIATION... 00Z TAFs: VFR conditions are expected to continue through the TAF period except KEAT. There will be elevated showers that move through the region late this evening and overnight. There is a small chance (10-15% chance) of sprinkles) from 06-15Z for most TAF sites as a vort max moves through. Chance of TS out of these is very low (5%) but cannot be ruled out. Bands of convection will form in the Cascades in the very late morning to early afternoon and eventually SE WA and southern ID Panhandle around 23-00z. Confidence is too low for TS in the TAF but there is a 10-20% chance around 00z for KLWS-KPUW-KEAT. Vsbys at KEAT will degrade this evening around 07-08z as northwest winds bring in smoke from the Little Giant Fire. South to southwest winds will increase in the Columbia Basin, Palouse, and Spokane area in the late morning to early afternoon. FORECAST CONFIDENCE AND/OR ALTERNATE SCENARIOS: Low confidence for TS impacts before 0Z for KEAT-KLWS-KPUW. ----------------------- 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 68 94 59 82 54 87 / 10 10 20 0 0 0 Coeur d'Alene 68 95 60 81 53 86 / 10 10 40 0 0 0 Pullman 62 91 51 78 46 86 / 10 10 30 0 0 0 Lewiston 72 98 62 87 59 92 / 10 10 40 0 0 0 Colville 60 95 52 81 45 87 / 10 10 40 10 0 0 Sandpoint 62 93 56 77 47 83 / 10 20 40 10 0 0 Kellogg 63 92 55 77 52 84 / 10 10 40 0 0 0 Moses Lake 69 95 56 85 54 89 / 10 10 0 0 0 0 Wenatchee 76 94 63 83 62 88 / 20 20 0 0 0 0 Omak 71 96 56 85 56 88 / 10 20 20 10 0 0 && .OTX WATCHES/WARNINGS/ADVISORIES... WA...Heat Advisory until 10 PM PDT this evening for Central Chelan County-Lower Garfield and Asotin Counties-Moses Lake Area- Northeast Blue Mountains-Northeast Mountains-Okanogan Highlands-Okanogan Valley-Spokane Area-Upper Columbia Basin-Washington Palouse-Waterville Plateau-Wenatchee Area-Western Okanogan County. Red Flag Warning from 4 PM Saturday to 11 AM PDT Sunday for Selkirk Mountains of Northeast Washington (Zone 700). Red Flag Warning from noon to 10 PM PDT Saturday for Colville Reservation (Zone 702)-Eastern Columbia Basin -Palouse - Spokane Area (Zone 708)-Foothills of Central Washington Cascades (Zone 705)-Foothills of Northeast Washington (Zone 701)-Lower Palouse -Snake River (Zone 709)- Waterville Plateau (Zone 706)-Western Columbia Basin (Zone 707). Air Quality Alert until 2 PM PDT Monday for Central Chelan County-Okanogan Highlands-Okanogan Valley-Upper Columbia Basin-Waterville Plateau-Wenatchee Area-Western Chelan County-Western Okanogan County. Red Flag Warning from 11 AM Saturday to 8 AM PDT Sunday for East Portion of North Cascades National Park/Lake Chelan National Recreation Area (Zone 697)-East Washington Central Cascades (Zone 696)-East Washington North Cascades (Zone 698)-Methow Valley (Zone 704)-Okanogan Highlands and Kettle Mountains (Zone 699)-Okanogan Valley (Zone 703). ID...Heat Advisory until 10 PM PDT this evening for Central Panhandle Mountains-Coeur d'Alene Area-Idaho Palouse- Lewis and Southern Nez Perce Counties-Lewiston Area- Northern Panhandle. Red Flag Warning from 4 PM Saturday to 11 AM PDT Sunday for Northern and Central Idaho Panhandle (Zone 101). && $$  266 FXUS64 KSHV 220004 AFDSHV Area Forecast Discussion National Weather Service Shreveport LA 704 PM CDT Fri Aug 21 2026 ...New AVIATION... .KEY MESSAGES... Issued at 1238 PM CDT Fri Aug 21 2026 - Thunderstorms across the southern half of the ArkLaTex this afternoon and evening will be capable of producing damaging wind gusts. - Showers and storms tomorrow afternoon may produce damaging wind gusts and large hail in southwest Arkansas and immediately adjacent portions of Oklahoma, Texas and Louisiana. - A Heat Advisory will continue areawide overnight and through tomorrow evening for high temperatures near or in excess of 100 degrees with heat indices up to 109 continuing throughout the week ahead. && .DISCUSSION... Issued at 1238 PM CDT Fri Aug 21 2026 Decaying showers along the I-30 corridor are at this hour still trying to put down some strong gusts. As these deteriorate, attention will turn this afternoon to the surface boundary sliding south. Recent runs of CAMs indicate convection lighting up by mid to late afternoon south of the I-20 corridor in east Texas and north Louisiana, prompting an upgrade to Slight Risk (Level 2 of 5) by the SPC. As with yesterday's storms, the primary threat will be wind- driven in nature, likely in the form of downbursts produced by mature to decaying storms or storm complexes. Today's storms look to move south out of the area by late evening, leaving the region generally dry overnight, aside from the potential arrival of the leading line of the next complex out of Oklahoma along and north of I-30 in the pre-dawn hours. These storms will continue to graze our northern zones into tomorrow morning, with subsequent rounds of storms to follow. The latest NBM guidance keeps PoPs primarily north of the I-20 corridor through Sunday morning, based on the steering of northwest flow aloft and impulses of moisture being driven south. As for the heat outlook, solutions are staring to diverge more, but the overall trend is minor relief from the oppressive heat and humidity of recent days. CONSShort is favoring significant mixing out of dewpoints tomorrow behind the passing surface boundary. While this may be exaggerated, even the comparably muggy NBM numbers do not indicate ArkLaTex sites exceeding Heat Advisory criteria, and some of our northern sites struggling to even reach criteria. Allowing for potential overperformance, extended areawide Heat Advisory through Saturday evening. The long term forecast is considerably more uncertain, based on the extent and strength of the upper level ridge and high pressure. As of this writing, Sunday looks to remain largely dry, with scattered chances for showers and storms clipping our northern and eastern zones going into next week, a bit of a drier period late Monday through early Wednesday, and more rounds of showers and storms for the latter half of next week as weak disturbances are swept south on the northwest flow. In a nutshell, the prevailing upper level pattern will change very little, but the exact position of the northwest flow and moisture impulses will be the deciding factor in who gets rain and when. Triple digits look to continue throughout, though the presence of more frequent rainfall and cloud cover may start to make a dent in this prolonged heat wave for our northeastern zones, meaning highs "only" in the middle to upper 90s. Lows in the middle to upper 70s will likewise continue throughout. /26/ && .AVIATION... (00Z TAFS) Issued at 644 PM CDT Fri Aug 21 2026 For the 22/00Z TAF period, convection across our southern airspace will gradually wind down over the next few hours this evening with some convective debris clouds lingering overnight. Another round of afternoon convection will be possibleon Saturday as a frontal boundary continues to linger across the region so have included a mention of VCTS at all sites once again later in the TAF period. Otherwise, VFR conditions should prevail outside of any convection with light and variable winds expected through the period except for much higher gusts likely invof strong to severe convection. /19/ && .SPOTTER INFORMATION STATEMENT... Issued at 1238 PM CDT Fri Aug 21 2026 Spotter activation may be needed this afternoon and evening for East Texas and North Louisiana with the development of thunderstorms that may produce damaging wind gusts. && .PRELIMINARY POINT TEMPS/POPS... SHV 77 101 77 100 / 20 10 20 10 MLU 75 102 75 100 / 10 20 20 10 DEQ 71 99 70 98 / 30 30 20 10 TXK 76 100 74 99 / 10 20 30 10 ELD 73 100 72 99 / 10 20 30 10 TYR 79 103 79 103 / 20 10 10 10 GGG 77 104 77 103 / 20 10 10 10 LFK 77 103 77 101 / 20 10 10 10 && .SHV WATCHES/WARNINGS/ADVISORIES... AR...Heat Advisory until 8 PM CDT Saturday for ARZ050-051-059>061-070- 071. Extreme Heat Warning until 9 PM CDT this evening for ARZ072-073. Heat Advisory until 8 PM CDT Saturday for ARZ072-073. LA...Extreme Heat Warning until 9 PM CDT this evening for LAZ001>006- 010>014-017>022. Heat Advisory until 8 PM CDT Saturday for LAZ001>006-010>014- 017>022. OK...Heat Advisory until 8 PM CDT Saturday for OKZ077. TX...Heat Advisory until 8 PM CDT Saturday for TXZ096-097-108>112. Extreme Heat Warning until 9 PM CDT this evening for TXZ124>126- 136>138-149>153-165>167. Heat Advisory until 8 PM CDT Saturday for TXZ124>126-136>138- 149>153-165>167. && $$ DISCUSSION...26 AVIATION...19  455 FXUS61 KGYX 220007 AFDGYX Area Forecast Discussion National Weather Service Gray ME 807 PM EDT Fri Aug 21 2026 .WHAT HAS CHANGED... No significant changes to the forecast were needed. && .KEY MESSAGES... 1. Mainly dry weather continues through tonight with cooler and unsettled weather this weekend. 2. A slow moving system will continue shower chances into early to mid week, with widespread measurable rainfall unlikely. && .DISCUSSION... KEY MESSAGE 1 DESCRIPTION... Mostly dry conditions are expected to continue through tonight as high pressure sits overhead this afternoon. The high will then begin shifting to the northeast tonight as it gives way to multiple low pressures that will move across Northern New England this weekend. For tonight, other than the coast and southern NH, skies should stay mainly clear, allowing temperatures to fall into the 50s south of the mountains with some 40s to the north. More valley fog is likely along the CT River, and I do have some low PoPs (20%) in southeast NH as some models indicate a few showers are possible overnight. The first low then approaches from the south Saturday morning with skies becoming mostly cloudy, generally in a south to north progression through the day as the low carries higher moisture into the area. It will also bring scattered showers (with dry periods as well), although models have been struggling on a run to run basis regarding timing, coverage, and location of showers. Looking at latest guidance, global models indicate broad lift over the Gulf of Maine approaching the coast and southeast NH in the morning and early afternoon, which will the primary areas to watch for showers. Lift spreads northward through the afternoon and evening (mostly across western ME), bringing increasing chances for showers, and the 12Z NAMNest and HRRR are generally on board with this scenario. Rainfall accumulations are expected to remain light, but parts of western ME could pick up over 0.25" of rain through Saturday evening. More uncertainty exists Saturday night into Sunday morning. Some models favor a lull in the showers due to some mid-level drying while the low-levels remain nearly saturated, suggesting fog (possibly dense) and precipitation that falls more in the form of drizzle. Others indicate another wave of low pressure, which would bring more in the way of showers and less in the way of fog. Due to the uncertainty, PoPs of 20-40% continue to be advertised. Sunday remains cloudy and dreary for most with scattered showers possible at times in the morning. Another low pressures tracks across Quebec that will send a cold front in from the west, resulting in another increase in shower chances and possibly a storm or two in the afternoon and evening hours. Some showers continue into Sunday night, but these should diminish south of the mountains from west to east overnight behind the front. KEY MESSAGE 2 DESCRIPTION... Closed low moving east of the Great Lakes will continue to pivot into southern Quebec Monday. Showers in the morning exit northeast across southern ME, with thinning clouds across NH. An embedded wave in the low's circulation will lift north through the morning, with building instability through mid afternoon. This could result in a rejuvenated shower/thunderstorm chance. The thunderstorm parameter space has some ingredients going for it, but also limitations. 0-6km shear of around 50 kts is abundant on the periphery of the broad low, and this overlaps with marginal surface CAPE early Monday. Low and mid level lapse rates would both be supportive of convection, however its possible dry air aloft will have increased significantly. Will keep the mention of iso to sct showers/thunder in the forecast at this time. Tuesday may see further influence of the closed low, with a return of moisture producing a continuation of cloud cover with the chance of showers. These showers take advantage of daytime heating, likely more diurnally driven than associated with a front. They may also be more widespread than the current forecast carries, but will see how timing and influence of the closed low trends. The low finally loses its grasp on New England come midweek as it nudges northeast into the Canadian Maritimes. This would provide a break from the dreary conditions as temperatures remain seasonable. && .AVIATION /00Z SATURDAY THROUGH WEDNESDAY/... Through Saturday...VFR prevail for most areas tonight, but valley fog is expected again with local IFR or lower conditions. This will be true at both LEB and HIE again tonight. VFR conditions prevail Sat, but by mid to late afternoon CIGs will be lowering and MVFR conditions are anticipated. It is possible that some IFR CIGs work into coastal areas by evening along with some rain showers. Outlook: Rest of Saturday-Saturday night: Increasing chances for showers, and a lowering of ceilings from south to north is likely with many sites reaching at least IFR, but LIFR is possible, especially going into Saturday night. Fog is also likely Saturday night. Timing of restrictions remains uncertain, but most likely time to start seeing IFR is Saturday afternoon into Saturday evening. Sunday: Fog lifts in the morning, except may linger at RKD much of the day. Ceilings may remain IFR to even LIFR for most sites, especially in western ME, although NH terminals could reach MVFR by the afternoon. Showers remain likely over much of New England. Sunday night: IFR to LIFR restrictions remain likely due to fog, low stratus and showers. Some improvement from west to east is possible overnight, but that remains uncertain. Monday: MVFR cigs possible, improving towards VFR as the day continues. SHRA possible across the interior. Monday Night: Less SHRA chances, VFR to MVFR cigs Tuesday: SHRA develop during the day with MVFR cigs possible as a closed low moves overhead. Tuesday Night and Wednesday: Improvement to VFR with no sig wx. && .MARINE... Through Sunday night...High pressure will lift northeast of the waters through tonight as multiple weak low pressures or surface troughs approach from the south and move across the waters this weekend, bringing increase chances for showers and fog. Northeast winds may briefly approach SCA levels Saturday but are otherwise expected stay below SCA levels. Another low crosses Quebec Sunday night and is expected to send a cold front into the waters overnight and toward daybreak Monday. Closed area of low pressure will push towards New England into the beginning of next week bringing a broad wind field. Gusts should remain below SCA criteria, but expect gradually building waves 2 to 4 ft through midweek. && .GYX WATCHES/WARNINGS/ADVISORIES... ME...None. NH...None. MARINE...None. && $$ DISCUSSION...Combs/Cornwell AVIATION...Legro  453 FXUS62 KTBW 220007 AFDTBW Area Forecast Discussion National Weather Service Tampa Bay Ruskin FL 807 PM EDT Fri Aug 21 2026 ...New UPDATE, AVIATION... .KEY MESSAGES... - Hot and humid conditions continue through the weekend. - Drier air aloft for Saturday will lead to lower rain chances. && .UPDATE... Issued at 800 PM EDT Fri Aug 21 2026 No changes planned for the evening update. Lingering batch of stratiform rain over eastern Polk County continues to diminish, otherwise dry conditions prevail across W FL. Residual boundaries from earlier convection may spark an additional shower or perhaps a storm through the evening, but activity is expected to continue winding down across the peninsula through the evening. A plume of drier mid level air advecting NE across much of the peninsula on Saturday is likely to limit convective coverage, with PoPs mainly 30% or less for areas outside of parts of the Nature Coast and perhaps parts of interior S FL. While typical summertime heat and humidity continues, heat indices are expected to largely remain below advisory levels, with highs around 90 immediate coastal and lower to mid 90s elsewhere. && .DISCUSSION... Issued at 219 PM EDT Fri Aug 21 2026 Very limited showers and thunderstorms continue to move eastward this afternoon, though some hi-res guidance does show additional storms flaring up over the interior later this evening. The overnight period will be quiet, then onshore flow will bring early showers and storms for the Gulf and coastal areas from around Tampa Bay northward. Previous discussion modified...Drier air aloft will remain over the area Saturday, which will aid in suppressing convection. Onshore west to southwest flow will push the west coast sea breeze inland with scattered showers and thunderstorms developing mainly over the interior during the afternoon and evening hours. On Sunday, southwest boundary layer flow ahead of a weak boundary across north Florida will enhance shower and thunderstorm activity over the northeast Gulf, which will advect onshore portions of the nature coast. Elsewhere, scattered showers/storms will develop over the interior during the afternoon as onshore flow persists. Continued hot with highs in the lower to mid 90s. Early next week, Monday will be a transition day with overall weak boundary layer flow which will allow the east and west coast sea breeze boundaries to push slowly inland through the day, likely colliding over the interior late in the day which will be the focus for highest pops. On Tuesday, light southeast boundary layer flow will develop which will hold the west coast sea breeze boundary closer to the coast. Slightly lower deep layer moisture will hold daily pops below climatic normals. Deep layer moisture will begin to recover over the southern forecast area mid week which will increase pops over southwest Florida, with slightly lower pops north and central. Temperatures will continue to run several degrees above climatic normals. && .AVIATION... (00Z TAFS) Issued at 730 PM EDT Fri Aug 21 2026 Mostly VFR expected through the period. Lgt/vrb to W-SW winds overnight increase out of the W-SW late morning, to generally 10 knots or less. Drier air aloft advecting over the peninsula will limit shower/storm chances, with PROB30 groups for potential impacts across terminals in the afternoon. && .MARINE... Issued at 219 PM EDT Fri Aug 21 2026 West/southwest winds will remain over the waters for the next several days, with no headlines expected. Scattered showers and storms are forecast each day, mainly during the overnight and morning hours. && .FIRE WEATHER... Issued at 219 PM EDT Fri Aug 21 2026 No fire weather hazards are expected as sufficient moisture will keep minimum afternoon relative humidity values well above critical levels for the next several days. Isolated to scattered showers and storms will develop over coastal areas in the morning, eventually spreading inland for the afternoon and evening. && .PRELIMINARY POINT TEMPS/POPS... TPA 80 91 80 90 / 10 20 40 50 FMY 79 94 78 94 / 10 20 10 30 GIF 76 95 75 93 / 20 10 20 60 SRQ 78 92 78 91 / 0 10 20 40 BKV 74 92 74 91 / 10 30 40 50 SPG 81 91 80 89 / 10 20 40 50 && Sea Breeze Thunderstorm Regime For Saturday: 4 Sea Breeze Thunderstorm Regime For Sunday: 4 For additional information on sea breeze regimes, go to: https://www.weather.gov/tbw/ThunderstormClimatology && .TBW WATCHES/WARNINGS/ADVISORIES... FL...None. Gulf waters...None. && $$ UPDATE/AVIATION...Hurt DISCUSSION/MARINE/FIRE WEATHER...Carlisle DECISION SUPPORT/UPPER AIR/CLIMATE...Flannery  490 FXUS62 KCAE 220007 AFDCAE Area Forecast Discussion National Weather Service Columbia SC 807 PM EDT Fri Aug 21 2026 .WHAT HAS CHANGED... A severe thunderstorm watch has been issued for the entire CWA until 9 PM EDT. Thunderstorms will develop this afternoon and could produce damaging winds and localized flash flooding. 18z Aviation. && .KEY MESSAGES... - 1. Severe weather and flash flooding possible today. && .DISCUSSION... KEY MESSAGE 1: Severe weather and flash flooding possible today. The severe weather threat is winding down across the forecast area this evening. There were numerous strong to severe thunderstorms across the area this afternoon, with the bulk of them shifting eastward as of this writing. There is an interesting cluster of storms developing in the rain cooled air in Calhoun/Orangeburg/Clarendon counties right now, so the storms are likely to persist for a bit in our eastern counties. But in general, things should be winding down over the next couple of hours. An upper trough will dig in on Saturday, with the axis shifting farther east. This will allow direr air to begin moving into the western portion of our FA this weekend. However, deeper moisture and moderate conditional instability along the coast could support another threat along the coast for microbursts and damaging winds in the afternoon, particularly near the I-95 corridor. Beyond that, a more seasonal pattern is expected to develop, with temperatures closer to normal, increasing humidity, and daily chances for isolated to scattered showers and thunderstorms. && .AVIATION /00Z SATURDAY THROUGH WEDNESDAY/... VFR conditions are present at all TAF sites currently as convection and stratiform rainfall pushes eastward and out of the forecast area. IFR and LIFR ceilings (and possibly visibilities) are forecast later tonight and into Saturday. Convection continues to push eastward out of the forecast area, leaving the TAF sites sitting underneath VFR cloud cover. While there was a lot of rainfall in several parts of the forecast area, the heaviest rain generally avoided all of the TAF sites. Despite that, there is still copious moisture across the area and the whole area is basically sitting within rain cooled air. The boundary will slowly shift southward tonight, maybe sparking a few showers closer to Columbia and CUB as it moves out of the upstate. Think this threat is low enough to keep it out of the TAFs at this point. The real threat to aviation tonight appears to be the development of ceiling or visibility restrictions later tonight. Weak subsidence aloft is expected to act on a moisture rich boundary layer and likely yield low ceilings. Vis restrictions are tougher to pin down. The sites that are more prone to fog in regular conditions are more likely to see fog with the stratus but the stratus should be more predominant at all sites regardless. Expecting this to persist through about late morning, with clouds clearing by early afternoon Saturday. Westerly and southwesterly winds are expected on Saturday. EXTENDED AVIATION OUTLOOK...Thunderstorm chances remain into the weekend, with scattered to widespread convection expected. && .CAE WATCHES/WARNINGS/ADVISORIES... SC...None. GA...None. && $$ DISCUSSION...ND/PL AVIATION...PL  531 FXUS63 KARX 220008 AFDARX Area Forecast Discussion National Weather Service La Crosse WI 708 PM CDT Fri Aug 21 2026 .KEY MESSAGES... - Scattered storms possible in southwest Wisconsin early this afternoon, some of which may be on the stronger side. - Seasonal temperatures continue into next week with highs in the 70s to lower 80s. - Dry weekend with the next potential round of storms coming Tuesday and Wednesday of next week. && .DISCUSSION... Issued at 1220 PM CDT Fri Aug 21 2026 Early this Afternoon: Storm Potential As of midday, our weak cold front stretches along a line from near Oelwien, IA to east of Eau Claire, WI. Forecast profiles in the prefrontal airmass show ample instability on the order of 2000-2500 J/kg of MLCAPE, but the wind profiles--while linear to the southeast--will initially struggle to support organized convection given that the stronger mid to upper level flow looks to not arrive until 21-00Z. By the time the stronger flow arrives and the hodographs elongate, the front will have progressed out of the forecast area and taken the severe weather threat with it. Therefore, while one cannot rule out a pulse storm capable of producing lower end severe hail in southwestern Wisconsin between 18-21Z, the main severe weather threat window for the day continues to look to be just to the south and east of the forecast area. It is also worth noting the 175-200 J/kg of 0-3-km CAPE available in southwestern Wisconsin ahead of the front. If a local surface vorticity max were to co-locate under an updraft for a prolonged period of time, we could see landspout processes in play. Saturday - Midweek: Dry Early, Storms Return Tuesday Northwest flow returns to the region for the weekend as a trough amplifies to our east and the ridge sets up to our west. This ridge decays as it moves eastward into early next week. With our region in between these two features and under the influence of surface high pressure, we look to be mostly dry and slightly cooler through the weekend until the ridge breaks down on Tuesday. High temperatures stay in the low 70s to low 80s from Saturday through Monday. It will not be until Tuesday as a shortwave crests the flattening ridge that the next risk for storms arrives with the medium range ensembles in good agreement (60-80%) that there will be storms during this period. The exact timing and placement details of this rain will be hammered out as we get closer to the event. Beyond Tuesday, the forecast is looking relatively dry for the middle to latter part of next week as the upper level ridge rebuilds to our west. && .AVIATION /00Z TAFS THROUGH 00Z SUNDAY/... Issued at 650 PM CDT Fri Aug 21 2026 Moderate (60-80%) for VFR through the 22.00Z TAF period outside of Wisconsin River Valley FG affecting KOVS. While low confidence (<15%) due to northwest winds ushering in a locally drier airmass, Mississippi River Valley FG affecting KLSE TAF site would be short lived and limited impact should low level saturation manage to come to fruition overnight into Saturday morning. Northwest winds increase through Saturday. && .ARX WATCHES/WARNINGS/ADVISORIES... WI...None. MN...None. IA...None. && $$ DISCUSSION...Skow AVIATION...JAR  860 FXUS63 KJKL 220010 AAA AFDJKL AREA FORECAST DISCUSSION...UPDATED National Weather Service Jackson KY 810 PM EDT Fri Aug 21 2026 .KEY MESSAGES... - A series of cold fronts will bring a possibility of showers and thunderstorms to the area at times through Saturday. - Some storms on Saturday afternoon and evening could produce strong to locally damaging wind gusts and even some hail. - Noticeably cooler and less humid air will arrive to start the new week, with mainly dry weather. && .UPDATE... Issued at 725 PM EDT FRI AUG 21 2026 23Z sfc analysis shows weak high pressure over eastern Kentucky and this is working to keep the winds light and clear the skies as the isolated showers continue to fade out. Currently, temperatures are running in the upper 70s to low 80s with some valleys reporting mid 70s. Meanwhile, amid light and variable winds, dewpoints are in the mid 60s to lower 70s - highest and stickiest south. Have updated the forecast mainly to add in the latest obs and trends for the T/Td/Sky grids but also to drop the PoPs off through the rest of the evening and overnight. These minor adjustments have been sent to the NDFD and web servers along with a freshening of the HWO, SAFs, and zones. && .SHORT TERM...(This evening through Saturday night) Issued at 330 PM EDT FRI AUG 21 2026 Puffy cumulus are bubbling up across eastern Kentucky this afternoon, with a few of them maturing into widely scattered showers and even a few isolated thunderstorms. That aside, temperatures are on the mild side for late August, with readings ranging in the low to mid 80s outside of convection. At the surface, a weak wave of low pressure is traversing far southeast Kentucky along a wavy cold frontal boundary. Aloft, 500 hPa troughing is in place over the Great Lakes and Ohio Valley with an embedded vort max just upstream over central Kentucky. A second notable 500 hPa vort max is dropping into the trough from northwestern Ontario. It is attended by a weak surface low over Lake Superior from which a cold front sweeps out an arc, first southwestward to along the Iowa/Nebraska border and then west-northwest to along the northern Rockies. The ongoing isolated to scattered convection is likely to increase slightly in coverage over the next hour or two before gradually diminishing with the loss of daytime heating as we head through the evening. As the wavy frontal boundary finally sinks well south of the area, clearing skies, light winds, and ample moisture will set the stage for renewed radiational fog formation overnight, especially in typical sheltered valley locations, though at least patchy fog may develop elsewhere. It will be seasonable, with temperatures dipping back into the mid 60s in most spots. Looking ahead to Saturday, the second vort max will carve a deeper parent trough as it presses into the Lower and Mid-Ohio Valley. This will be attended by the surface cold front, which is currently favored in short-range model guidance to pass through eastern Kentucky during the ~5 PM to midnight timeframe. Ahead of this boundary and upper-level disturbance, strengthening flow aloft will yield 30 to 40 kts of EBWD while good heating is favored to build 2000 to 3000 J/kg of MUCAPE Saturday afternoon. With ample dry air aloft and DCAPE values near or over 1000 J/kg, downdrafts capable of producing strong to damaging winds will be possible on an isolated scale. Additionally, the CAPE profile is well-proportioned within the hail growth zone and hodographs are relatively straight. Therefore, if any of the stronger cells can adopt supercellular characteristics, isolated hail is also a reasonable secondary possibility. Accordingly, SPC has maintained a Marginal Risk (1/5) for damaging winds and large hail across nearly all of the JKL CWA. Heading into Saturday evening and night, convection should diminish as the front and upper-level disturbance depart. In their wake, clearing skies and light winds will once again set the stage for at least some fog in the valleys, though weak low-level northwest flow will be a mitigating factor. Saturday night's low temperatures are forecast to range in the low to mid 60s. .LONG TERM...(Sunday through Friday) Issued at 330 PM EDT FRI AUG 21 2026 The long term period will start with a relatively comfortable air mass in place, by August standards. Surface high pressure supplying the cooler and drier air should be ridging from western Ontario to the lower Ohio Valley, while low pressure (surface and aloft) is just north of the Great Lakes. The upper trough surrounding the low will cover most of the eastern CONUS. Our lowest dew points from this air mass are forecast from Monday into Tuesday, with readings in the 50s, also allowing for lows in that range. In fact, the NBM and MEXMOS are only a couple degrees off the record of 55 at JKL on the 25th. The low and the trough weaken by midweek as they drift east, and a warming trend gets underway locally as geopotential heights rise. The forecast then gets messier moving into the late week time frame. Another upper low or trough is expected to move east southeast to southeast Ontario, which will deepening a larger scale upper trough over the eastern CONUS again. This supports a cold front to move southeast through the Midwest. There is not agreement on the timing of this front to arrive here, or on the surface pattern setting up in advance. At this point, only a generalized forecast is practical, with an increase in moisture/dew points and POP ahead of the front late in the week. && .AVIATION...(For the 00Z TAFS through 00Z Saturday evening) ISSUED AT 810 PM EDT FRI AUG 21 2026 Limited convection will continue to dissipate through the rest of the evening with the loss of diurnal heating. Thereafter, valley fog should again develop and may affect a few of the TAF sites generally during the 06Z to 12Z timeframe. As for winds, outside of any storms, they will generally be light and variable. && .JKL WATCHES/WARNINGS/ADVISORIES... None. && $$ UPDATE...GREIF SHORT TERM...GEERTSON LONG TERM...HAL AVIATION...GEERTSON/GREIF  814 FXUS65 KBOU 220010 AFDBOU Area Forecast Discussion National Weather Service Denver/Boulder CO 610 PM MDT Fri Aug 21 2026 .KEY MESSAGES... - Heat eases, along with an increase in shower and storm coverage this weekend. - Gusty outflow winds from a few high based showers/storms into this evening. Isolated severe storm threat over the plains. - Highest coverage of showers and storms expected Saturday, along with a few severe storms on the plains Saturday and then again Sunday. - Gradual drying next week, but continued storm chances through at least Wednesday or Thursday. Slight cooling but temperatures still above normal. && .DISCUSSION /Through Friday/... Issued at 1258 PM MDT Fri Aug 21 2026 It's a hot one today with temperatures early this afternoon already in mid to upper 90s along the I-25 Corridor, and approaching records in some spots (Denver's record is 99F set in 2023). There was some slight relief over the northeast plains due to outflow from earlier Nebraska convection, so temperatures have been running a few degrees below expectations there. Given the strong surface heating and steep low/mid level lapse rates along the Front Range, we are seeing high based convection develop. These will be capable of producing strong microburst winds as DCAPE has grown into the 1400-1600 J/kg range. Meanwhile, farther east the low level moisture is holding steady with dewpoints in the lower to mid 60s in the easterly flow. While this easterly surge is expected to weaken during peak heating, it will provide for higher instability and a richer storm environment should storms be able to fire. Thus, a couple severe storms will be possible through this evening over the northeast plains given MLCAPE of 1200-2000 J/kg and bulk shear near 30 kts. For Saturday, monsoonal moisture will increase as the upper level ridge axis tilts ever so slowly eastward. Precipitable water values are forecast to reach near 150% of normal. However, the airmass is quite warm so we think most storms that originate over the mountains and then push onto the I-25 Corridor in the afternoon will still be relatively high based, and thus mostly outflow dominated. We think the majority of the storms with more widespread and beneficial rains will develop just east of the I-25 Corridor where outflows intersect with a richer low level environment. That's where HREF ensembles show higher concentration of stronger storms. Locally heavy rain totals upwards of 1.5-2 inches will be possible there, and potentially the Palmer Divide, based on the environment and HREF Local Probability Matched Means (LPMM). Meanwhile, there will also be a threat of a few severe storms as MLCAPE once again grows to 1200-2000 J/kg and bulk shear of 25-35 kts is forecast. For Sunday, there is good agreement that the mid and upper levels will dry slightly as a more westerly component develops under a flattening ridge. Thus, storm coverage should decrease a little, in the absence of any forcing mechanisms. A few severe storms will once again be possible across the plains as we expect sufficient low level moisture and instability, with the greatest risk once again hovering just east of the I-25 Corridor. For much of next week, deterministic forecasts and ensembles are averaging toward flat ridging and weak westerly flow aloft. That likely keeps us too zonal for deep monsoonal moisture, but just enough for scattered storms most afternoons and evening. While individual model runs vary, there is still potential for a weak backdoor cool front or two. They will offer up very little in the way of cooling, but should keep us a few degrees "cooler" (mostly lower 90s for highs on the plains and I-25 Corridor) versus the full on summer heat experienced today. Ensembles are supportive of a decrease in precipitable water (PW) by the end of next week, which would support less, or only isolated, storm possibilities and a return of much above normal temperatures. && .AVIATION /00Z TAFS through 00Z Sunday/... Issued at 609 PM MDT Fri Aug 21 2026 Storms are starting to move out of the vicinity of the TAF sites, but we can't rule out the possibility of more updrafts and gusty winds in the next few hours, especially with the current showers to the south and west sending out outflows. Because there's been so many scattered storms across the metro area, confidence is low as to where the winds will be in a few hours. Models show varying wind directions, though observations would suggest an easterly component. Of course, any further convection or outflows could shift the wind in variable directions. After storms move out of the area to the east, winds should start turning towards drainage, getting there by around 02Z and staying generally S/SW overnight. Winds turn northward again in the morning, around 15/16Z, and staying north/northeast until storms start to move through in the afternoon. Current model guidance has more moisture in the environment tomorrow afternoon than we had today, and the CAMs remain in fairly good agreement on convection initiating around 22Z and lasting through 06Z on Sunday. DCAPE values in the most recent model runs also look to have increased from previous runs, so gusty outflows will most likely be a concern for tomorrow's storms, as well. && .BOU WATCHES/WARNINGS/ADVISORIES... None. && $$ DISCUSSION...20 AVIATION...AGS  584 FXUS65 KRIW 220009 AFDRIW Area Forecast Discussion National Weather Service Riverton WY 609 PM MDT Fri Aug 21 2026 .KEY MESSAGES... - Scattered showers and isolated storms continue across the southwestern half of the area this evening. Showers will linger across western Wyoming overnight into Saturday morning. - Monsoonal moisture increases on Saturday with more numerous showers and thunderstorms, some may produce heavy rain and local flooding. Marginally severe weather looking more possible in the afternoon across Natrona/Johnson Counties, with damaging winds and small hail the main threats at this time. - Lingering moisture will bring a daily chance of showers and thunderstorms into early next week, with temperatures more seasonable for this time of year pushing towards the end of August. && .UPDATE... Issued at 1245 PM MDT Fri Aug 21 2026 Hottest of the afternoon still in progress, bumped up a few spots a couple degrees east of the Divide as it has already warmed past the previous noon forecast. Otherwise, much of the forecast still intact and on schedule. Monsoonal moisture visible on IR pumping up from the south, but more limited and a bit west than it was yesterday currently. This should extend into western parts of the state by mid-afternoon that will spark thunderstorm activity. HiRes models haven't been very reliable the past couple of days missing the morning showers across Johnson County and a bit late on development thus far. PoPs will be adjusted as needed once things kick off, but main concerns (if you want to call it that) is gusty outflows over 40 mph. A rogue storm or two could push down the Wind River Basin between 4-6PM with some of the models picking up on this still, although chances low around 15-20%. Even some isolated storms developing currently near South Pass with slow eastward movement due to weaker steering flow aloft. Not much should come from it but a mere breeze. Otherwise, weekend precipitation looks on track for now but maybe a bit stronger severe weather wise across eastern counties. HiRes models do indicate better instability and stronger multicellular formations across Natrona to Johnson County during the afternoon and early evening hours. Even though SPC pulled the Marginal further east, this should be back in place east of the Bighorns by Saturday morning if not having a slight closer to the eastern parts of the CWA. Stay tuned for updates overnight into early Saturday morning. && .DISCUSSION... Issued at 241 AM MDT Fri Aug 21 2026 We are now returning to my favorite (note sarcasm, this is by far the thing I hate the most about the weather around here) thing to forecast, the monsoon. And, the models are off to a bad start. We have some showers across northern Wyoming that none of the models had. So, they are 0 for 1 right now. And this isn't baseball where batting .300 makes you an all star. Other than these light showers, things are quiet right now, and it should stay this way through the morning. However, we will see another round of isolated showers and thunderstorms today, probably in similar positions to yesterday. Coverage should remain less than 1 out of 3 for all areas though, as some warm air aloft should prevent widespread convection. This is mainly across the western half of the state. Dewpoint depressions remain fairly high and we still have inverted-V soundings, so this will likely be another day of strong wind gusts from any shower or thunderstorm with only light rain. There could be a stray shower further east, but the chance is less than 15 percent so we left the forecast dry. But, let's just say my confidence is not high with how poorly the models handle the monsoon with weak forcing. Some showers will linger through the night across the west as well, but the core of the moisture likely holds off until Saturday. The other story today will be the heat, as temperatures will peak today as 700 millibar temperatures climb to around 20 Celsius. All areas below 6500 feet have at least a 4 out of 5 chance of high temperatures over 90 this afternoon. Areas below 5500 feet have at least a 1 in 2 chance of highs over 95. As for triple digits, it is smaller. However, temperatures have been running higher than guidance so I give it around a 1 in 3 chance in places like Greybull and Worland. The warmest temperatures would be east of the Divide with the lower elevations and more sunshine. The monsoon returns with a vengeance on Saturday. Precipitable water values climb to around 150 to 200 percent of normal across most of the area. We will also have a shortwave moving across the area to bring some additional forcing. The result will be a chance for all areas to see a shower or thunderstorm, but most guidance favors western Wyoming. There is a Marginal risk of Excessive Rainfall across areas west of the Divide as I write this around 1:15 am. This could be expanded east, we will know around 2:30 am. There is some steering flow, especially at 500 millibars, so this should mitigate the flooding threat somewhat but it will be there. Most convection should end by midnight, but some showers will continue after midnight. Confidence on placement of showers Saturday night is very low, as this is where the models have struggled the most with the monsoon. The best chance will be in western Wyoming, but exactly where is still somewhat uncertain. As for temperatures, they will remain very warm east of the Divide where there will be some morning sunshine, but about 5 degrees cooler than Friday. Areas west of the Divide should see a greater drop, with more cloud cover and a greater coverage of showers. And, some storms could become strong. We do have a Marginal risk of severe weather east of the Bighorn Range. It may be a bit overdone, since there is only weak shear. The main threat would be strong wind gusts, like most showers or storms in Wyoming. Monsoonal moisture then looks to stick around into the first part of next week. This will lead to daily chances of mainly diurnal showers and thunderstorms each day. Guidance has poor consistency with the details though. So, it is still difficult to nail down details on where the most numerous convection will be each day and timing of the storms. So, we kept things broad brushed for the most part. Temperatures will decrease somewhat with more cloud cover. However, with the mean ridge remaining in place, above normal temperatures should continue into next week. There are some indications that drier air may try to move in toward the end of next week, bringing a return to drier conditions for a few days through the weekend. && .AVIATION /00Z TAFS THROUGH 00Z SUNDAY/... Issued at 354 PM MDT Fri Aug 21 2026 Virga, showers, and thunderstorms will be present across western and central Wyoming, including in the area of or at KJAC, KRIW, KRKS, KLND, KPNA, and KBPI, through 06Z at the latest. Gusty outflows of 35 to 45kts are possible in and around any virga, showers, and thunderstorms. KCOD, KCPR, and KWRL have less than a 20 percent chance during this timeframe. Between 07Z and 18Z, model guidance is showing a cluster of showers moving across western and central Wyoming. Rain shower chances exists at all terminals except KRKS during this timeframe. However, confidence in exact timing and impacts is rather low so continued with the PROB30 groups. More widespread showers and thunderstorms are forecast Saturday afternoon at all terminals with the primary hazards being lightning, breezy winds, and heavy rainfall. Brief periods of MVFR flight conditions cannot be ruledout in any shower or thunderstorm this TAF period. Otherwise, VFR flight conditions are anticipated through 00Z Sunday with winds remaining 12kts or less. KCPR could see occasional gusts around 20kts Saturday afternoon outside of showers or thunderstorms. Please see the Aviation Weather Center and/or CWSU ZDV and ZLC for the latest information on smoke, icing, and turbulence forecasts. && .RIW WATCHES/WARNINGS/ADVISORIES... None. && $$ UPDATE...Lowe DISCUSSION...Hattings AVIATION...Gerhardt  049 FXUS65 KPIH 220013 AFDPIH Area Forecast Discussion National Weather Service Pocatello ID 613 PM MDT Fri Aug 21 2026 .KEY MESSAGES... - Heat Advisories Active Today: Heat Advisories remain in effect through this evening across lower elevations, where peak afternoon temperatures will reach the mid-90s to lower 100s. - Severe Microburst Risk Tonight (45–65 mph Gusts): Monsoonal moisture surging into deeply dry lower atmospheric layers (inverted-V profiles) will support evening and overnight thunderstorms capable of producing localized severe dry microburst wind gusts of 45 to 65 mph, especially across the lower Snake Plain, Magic Valley, and South Hills. - Widespread Saturday Storms & Fire Concerns: Convective coverage increases markedly on Saturday, introducing heightened fire weather concerns from lightning and erratic outflow winds before the main trough exits into Western Canada on Sunday. - Seasonable Late-August Trend Next Week: A modest ridge rebuilds next week, maintaining isolated afternoon monsoonal storm chances and near-normal temperatures in the mid-to-upper 80s. && .DISCUSSION... Issued at 134 PM MDT Fri Aug 21 2026 Unseasonably hot conditions continue across eastern Idaho this afternoon, with widespread lower-elevation Heat Advisories remaining active through this evening. Temperatures have climbed rapidly into the lower 90s and are on track to top out in the mid-90s, with localized readings exceeding 100°F across the lower Snake Plain and Magic Valley prior to peak heating. Mostly sunny skies will give way to increasing cloudiness late this afternoon and evening as a plume of monsoonal moisture surges northward through the Great Basin ahead of an upper-level trough entering the Pacific Northwest. High-resolution convective-allowing models (CAMs) continue to advertise elevated shower and thunderstorm development beginning this evening and lingering into the early overnight hours. Forecast soundings reveal deeply inverted-V thermal profiles across the lower boundary layer, creating an environment highly efficient at generating strong convective downdrafts. Stronger storms tonight will be capable of producing localized microburst wind gusts of 45 to 65 mph, with the highest threat centered across the lower Snake Plain, Magic Valley, and South Hills. Nocturnal showers and embedded storms will persist through the first half of the overnight period. Following a brief early-morning lull, a more widespread wave of showers and thunderstorms will overspread eastern Idaho on Saturday. The combination of widespread lightning strikes and gusty, erratic outflow winds will introduce elevated fire weather concerns across dry fuel beds. As the primary upper- level trough pushes northeastward into Western Canada on Sunday, large-scale forcing will wane, restricting lingering shower and thunderstorm chances primarily to the higher terrain. Subtropical high pressure over the Four Corners will slowly attempt to rebuild toward the Great Basin early next week. However, the ambient upper-level flow pattern will remain favorable for sending weak, periodic pushes of monsoonal moisture into the Intermountain West. This will maintain at least isolated afternoon and evening thunderstorm chances through mid-week. Because 500mb heights are forecast to remain modest, extreme heat is not expected to return next week. Daytime maximum temperatures will hold right around seasonal climatological norms for late August, topping out in the mid-to- upper 80s across lower elevations with only isolated spots briefly reaching 90°F. && .AVIATION /00Z TAFS THROUGH 00Z SUNDAY/... Issued at 510 PM MDT Fri Aug 21 2026 Main impact through this evening will be potential of showers and thunderstorms. Have vicinityshowers tonight at all sites outside of PIH. Have tempo showers at DIJ. Put in prob30 thunderstorm groups in all locations after 18Z on Saturday with a much better shot at thunder at all sites. && .FIRE WEATHER... Issued at 134 PM MDT Fri Aug 21 2026 Monsoon moisture is beginning to work its way back into Eastern Idaho today and will continue through this weekend. Isolated storms will begin to pop up across the area this afternoon and activity becomes a bit more widespread overnight, though how much lightning will continue into tonight is a bit more uncertain. Strong wind gusts to 60 mph will be the main concern with storms today and again tomorrow with portions of the area under a Marginal Risk for severe storms both days. As thunderstorms begin to fire on Saturday afternoon, coverage will also increase, so a RED FLAG WARNING has been issued for Fire Weather Zones 410, 422, 425, 427, 475, and 476 due to the scattered coverage. These will be a mix of wet and dry storms with some of the drier storms more likely up in the Central Mountains and storms becoming wetter farther east. This is also part of the reason for leaving FWZ 411 and 413 out of the RFW. Coverage in those two zones will be isolated to nearly scattered at times. Heading into Sunday, it will be breezy with wind gusts of 25 to 35 mph and min RHs still in the 15 to 20 percent range in the Central Mountains, so near-critical fire weather conditions will exist there again, but min RHs elsewhere will range from 20 to 30 percent. We will still see some isolated to nearly scattered thunderstorms on Sunday, too. In fact, this monsoon moisture will continue each afternoon through at least the first half of next week. && .PIH WATCHES/WARNINGS/ADVISORIES... Heat Advisory until 10 PM MDT this evening for IDZ051>059-061- 062-064-065-067-075. Red Flag Warning from noon to 9 PM MDT Saturday for IDZ410-422- 425-427-475-476. && $$ DISCUSSION...McKaughan AVIATION...GK FIRE WEATHER...Messick  114 FXUS61 KAKQ 220015 AFDAKQ AREA FORECAST DISCUSSION National Weather Service Wakefield VA 815 PM EDT Fri Aug 21 2026 .WHAT HAS CHANGED... Updated full discussion. No significant forecast changes. && .KEY MESSAGES... 1) Showers and storms late this evening into overnight will be capable of producing heavy rainfall, potentially leading to localized flash flooding. Additional showers and storms are expected Saturday, mainly near the bay and on the eastern shore. 2) Mainly dry with seasonable temperatures Sunday through Tuesday. Isolated to scattered diurnally driven convection returns by the middle to latter part of the week. && .DISCUSSION... As of 230 PM EDT Friday... KEY MESSAGE 1...Showers and storms late this evening into overnight will be capable of producing heavy rainfall, potentially leading to localized flash flooding. Additional showers and storms are expected Saturday, mainly near the bay and on the eastern shore. The cold front that crossed the area last night is now stationary and has settled just to our south. A broad upper trough is over the Great Lakes and extends south over the Appalachians. A lead shortwave on the SE side of the trough is crossing the Piedmont, and is responsible for the showers and isolated storms that are tracking across western portions of the FA despite only a few hundred J/kg of MUCAPE. Scattered strong to severe storms have developed near the front from south central to southeast NC. The front is progged to move back north tonight as a warm front and bisect the area by early Sat AM. As a result, expect numerous showers and a few tstms to develop/move across southern VA and NE NC during the evening, before gradually spreading N and NE overnight. The highest precip chances shift to areas near the Bay and the Eastern Shore by sunrise on Saturday. Given the moisture rich airmass in place (PWs of 1.7- 2.1"), locally heavy rain is likely this evening-tonight, and a few areas could see 2-3" in a short time (mainly south of I-64). A Flood Watch was considered, but feel that the highest totals will be localized enough (and storms will be moving fast enough) for flash flooding to be isolated in nature. The 12z/21 HREF has 10% probs for 3" in 3 hours for mainly S/SE portions of the area tonight. A few strong to severe storms can't be ruled out near/south of the VA-NC border between now-9 PM, but confidence is low. The front will continue to linger over east and northeast portions of the FA Saturday as the broad upper trough axis moves over the area. In addition, a weak surface low may develop along it in the vicinity of the Chesapeake Bay/Lower Eastern Shore. Additional showers and a few tstms are likely, especially from the Peninsulas to Eastern Shore. Convection will likely initiate earlier than usual and may even be ongoing during the morning. While the saturated profile and weak sfc heating (highs only in the low-mid 80s) should mitigate the severe wx potential, localized heavy rain/flooding is possible (especially near the bay and on the Eastern Shore). Similar to tonight, a few spots could see 2-3" of rain in a short time. WPC has maintained a Slight Risk of Excessive Rainfall for eastern portions of the area on Saturday. KEY MESSAGE 2...Mainly dry with seasonable temperatures Sunday through Tuesday. Isolated to scattered diurnally driven convection returns by the middle to latter part of the week. The weak front will finally move offshore, as the main upper level trough axis shifts offshore and surface high pressure builds into the SE CONUS. The surface high will usher in a drier airmass with seasonable temperatures in the 80s and dew points in the 60s Sunday into early next week. The high is progged to break down by Wed/Thu, with unsettled conditions and isolated-scattered aftn/evening convection returning mid to late week. && .AVIATION /00Z SATURDAY THROUGH WEDNESDAY/... As of 815 PM EDT Friday... A frontal boundary remains settled south of the area to start off the forecast period. Mainly VFR north with VFR to MVFR CIGs in SE VA/NE NC. Showers and isolated thunderstorms are currently along or just south of the VA/NC border. CIGs lower to 500-2000 feet (lowest at RIC) tonight as that front moves back to the north as a warm front. In addition, numerous showers/tstms are expected to develop and/or move across southern VA/NE NC. Precip chances (showers w/ isolated tstms) increase at RIC/SBY overnight but strong to severe storms aren't expected. Still, IFR VSBYs are possible in any heavier showers. Remaining unsettled on Saturday with additional showers/storms expected (best chance at ORF and ECG). CIGs gradually improve Saturday morning into early afternoon. Outlook: Eventually drying out later Saturday night and Sunday, with VFR conditions returning Sunday morning through Monday. && .MARINE... As of 230 PM EDT Friday... Key Messages: - Generally benign marine conditions expected through the weekend, outside of afternoon/evening thunderstorms. Afternoon weather analysis shows NNE wind prevailing around 10kt with gusts upwards of 15kt across the waters. Seas remain low at this time with wave heights around 1-2 ft across the bay and 2-3ft across our nearshore zones and 3-4ft further offshore. Winds are forecasted to shift later this afternoon and evening as a warm front lifts towards the area. Winds are expected to remain around 10kt with the shift and will be out of the E. In addition, the front will bring showers and thunderstorms that could pose the risk of wind gusts greater than 34kt and lightning. In terms of wave heights not expecting much change in them. By Saturday, southerly flow will return, then becoming SW by Saturday evening. Confidence continues to increase that a cold front will cross the waters late Sunday night allowing for northerly winds to return to our waters, These winds are forecasted to last through Monday. Low risk for rip currents is expected through the weekend and into Monday. && .AKQ WATCHES/WARNINGS/ADVISORIES... MD...None. NC...None. VA...None. MARINE...None. && $$ DISCUSSION...ERI AVIATION...AJB MARINE...HET  230 FXUS66 KMFR 220016 AFDMFR Area Forecast Discussion National Weather Service Medford OR 516 PM PDT Fri Aug 21 2026 ...Updated the Aviation and Marine Sections... .AVIATION...22/00Z TAFs...Marine stratus will persist tonight through Saturday night with mainly IFR along the coast and over the marine waters. Patches of LIFR will be at maximum coverage late tonight into early Saturday morning. Also, drizzle is possible along and west of the coastal ranges. Inland, VFR conditions will prevail. High clouds from the Cascades eastward will gradually shift north-northeastward, out of the area by late Saturday morning. Gusty winds will linger early this evening, and return for Saturday afternoon and evening. The strongest winds will be east of the Cascades and in the Shasta Valley, with south to west gusts today and southwest to northwest gusts on Saturday at 20 to 40 kt. Winds will ease after sunset. && .MARINE...Updated 830 PM PDT Friday, August 21, 2026...Light winds and low seas will persist into Sunday morning. Southerly winds will shift to westerly Saturday as a weak front dissipates over the waters. A thermal trough will develop Sunday with increasing northerly winds. These winds will likely be hazardous to small craft south of Cape Blanco late Sunday morning through Monday morning. The area of stronger winds is likely to shift offshore, beyond the inner waters, during Monday. Winds are then likely to diminish again later Monday night through Tuesday into Wednesday. && .PREV DISCUSSION... /Issued 252 PM PDT Fri Aug 21 2026/ KEY MESSAGES... * While marine stratus persists over coastal areas and clouds stream to the north inland, activity is unlikely this afternoon and evening. * A Red Flag Warning is in place for the Shasta Valley as well as Klamath and eastern Lake counties this afternoon and evening for gusty winds and low relative humidities (RHs). For Saturday afternoon and evening, a Red Flag Warning is in place across Klamath and Lake counties. * Winds ease on Sunday, with a generally unimpactful pattern expected for next week. DISCUSSION...A cutoff low passing to the west will guide area weather today and through much of the weekend. While marine stratus lingers along the Oregon coast and clouds are streaming from south to north over more inland areas, activity is not expected today (although virga may bring some hopes up). Radar returns show a line of higher returns over the Cascades and moving eastward, so a few stray showers are possible into parts of Klamath County. But with cloud cover limiting daytime heating, convective instability will be limited. Thunderstorms aren't entirely out of the question, but chances have trended downward for this afternoon and evening (5- 10%). With gusty winds and dry surface air being observed, a Red Flag Warning is in place for the Shasta Valley as well as across Klamath and eastern Lake counties. The low stats to swing inland over Washington state on Saturday. With drier air aloft, precipitation is not expected. Gusty southerly winds will move eastward, which will take the Shasta Valley out and put the rest of Lake County in a Red Flag Warning for Saturday afternoon and evening. Areas under marine stratus will see cooler temperatures while inland areas will be at seasonable temperatures. The cutoff low is expected to be to the northeast by Sunday, bringing a southwest flow pattern that will generally persist through the week ahead. A shortwave ridge is currently expected to bring temperatures 5-10 degrees above normal for Monday and Tuesday. An upper trough passing to the north will bring temperatures back down on Wednesday and Thursday, with elevated westerly winds over Lake and Modoc county terrain possible depending on its position. Deterministic models start to diverge into Friday and beyond, but meteograms show agreement that the rest of August looks to stay dry. -TAD FIRE WEATHER...Updated 130 PM PDT Friday, August 21, 2026...An upper level trough will pass through the region today into Saturday, bringing a period of increased winds and critical fire weather conditions. Afternoon winds increase today as the trough and associated dry cold front approach the region (gusts 25-35 mph), but daytime humidities will also trend somewhat higher compared to yesterday. Despite the uptick in humidities, it's close enough with the higher confidence on more widespread higher winds on Friday to warrant maintaining a Red Flag Warning for FWZs 281, 284, 285 and 624. Sustained winds won't quite reach criteria for FWZ 625 today, but by Saturday, however, 700 mb winds will peak in strength east of the Cascades and more widespread sustained winds of 15 to 20 mph are expected as the dry front passes. Additionally, daytime RHs will trend lower again, so another day of critical fire weather conditions is expected on Saturday. The Fire Weather Watch has been upgraded to a Red Flag Warning for FWZs 284/285/624/625 for gusty winds and low RH for Saturday afternoon/evening. In addition to wind/RH concerns for today and Saturday, there is the potential for isolated showers and very isolated thunderstorms today. Ample cloud cover so far is expected to limit daytime heating and instability, which should keep the lightning potential minimal today. There are some returns on radar this afternoon, but very little, if any, precipitation is making it to the ground. By Saturday, the mid-levels dry out and thunderstorm threat will shift well north of the forecast area into northern Oregon/Washington. More typical summer conditions return Sunday and persist into early next week. There are some signals for thunderstorm chances across eastern 285/625 on Monday, but much will depend on how far west the Four Corners High retrogrades behind this trough passage. Otherwise, another trough drops southward from the Gulf of Alaska and lingers off the BC coast through early next week. There will likely be additional shortwaves/troughs to swing through the region early next week, bringing periods of enhanced winds. Stay tuned for updates. /BR-y && .MFR WATCHES/WARNINGS/ADVISORIES... OR...Red Flag Warning until 9 PM PDT this evening for ORZ624-625. CA...Red Flag Warning until 9 PM PDT this evening for CAZ281-284-285. PACIFIC COASTAL WATERS...None. && $$  877 FXUS62 KMLB 220030 AFDMLB Area Forecast Discussion National Weather Service Melbourne FL 830 PM EDT Fri Aug 21 2026 ...New AVIATION... .KEY MESSAGES... Issued at 256 PM EDT Fri Aug 21 2026 - The typical Florida summertime pattern will persist locally through this weekend and into next week with daily afternoon showers and storms forecast across east central Florida. - Storm hazards today will include frequent to excessive lightning, strong wind gusts of 45-55 mph, small hail, and heavy downpours leading to rainfall accumulations of 1-3". There is a 5% chance for thunderstorm wind gusts up to 60 mph along the coast from the Cape northward. - Heat remains a concern across east central Florida, though peak heat indices are anticipated to stay below advisory criteria. Regardless, residents and visitors to the area are encouraged to practice heat safety! && .DISCUSSION... Issued at 256 PM EDT Fri Aug 21 2026 Current-Tonight... Satellite imagery shows a weak mid-level low along the northeast FL/southeast GA boarder this afternoon. Associated mid- level boundaries wrap the southern side of the low stretching across portions of northeast and central Florida. Despite some intrusion of dry air aloft, cloud cover and PWATs 1.9-2.0" suggest enough moisture to support at least scattered coverage of afternoon and evening storms. Environmental parameters remain similar to yesterday with cold 500mb temperatures around -7.5C and DCAPE values 800-1,200 J/Kg. Strong storms that develop again today will be capable of frequent to excessive lightning, wind gusts 45-55 mph, and small hail. The strongest storms should occur along boundary collisions, particularly collisions with the east coast sea breeze, and SPC has highlighted a Marginal risk for severe storms along the coast from the Cape northward. Here, there is a 5% chance for downburst wind gusts to 60 mph. Strong storms will also be capable of heavy downpours, and quick rainfall accumulations of 2-3 inches may result in minor or nuisance flooding. Showers and storms may linger a little bit into the evening across a few locations with dry conditions then forecast overnight. Saturday-Sunday... Pulses of shortwave energy continue to pass overhead this weekend as a mid-level trough slowly slides across the eastern U.S. A surface front remains stationary across the southeast while a surface ridge axis holds near or across south Florida. This will keep light offshore flow in place, predominantly out of the southwest. A drier airmass will favor slightly below normal rain chances for much of east central Florida on Saturday (~20-40%). Major global models then become split on moisture and rain chances on Sunday. Have shown a slight upward trend in Sunday's rain chances with this forecast package, suggesting more seasonal coverage of scattered afternoon showers and storms (40-60%). However, slightly lower forecast confidence exists due to wide model discrepancy. Cold temperatures aloft (~ -8C @ 500mb), high DCAPE (900+ J/kg), and efficient surface heating should allow for a few strong storms to develop each afternoon, and storms will be capable of frequent lightning, gusty downburst winds of 40-55 mph, and small hail. Heavy downpours within slow moving storms may result in localized nuisance flooding. Outside of showers and storms, near to slightly above seasonal temperatures are forecast. Highs mostly in the low 90s locally reach the mid 90s across portions of the interior. Trends continue to hold below Heat Advisory criteria with peak heat index values forecast to range 100-106F. Monday-Thursday... Troughing across the eastern U.S. gradually broadens as low pressure weakens and lifts northeast through portions of Canada. Surface ridging becomes reestablished across central Florida, and a loose pressure gradient will maintain light southerly winds, often becoming variable early each day. Winds shift onshore around 10 mph as the sea breeze develops each afternoon. Below seasonal rain chances are forecast early in the week before a more typical pattern of scattered afternoon and evening storms returns generally from Wednesday onward (~40-60%). Temperatures show little change, persisting in the low to mid 90s each afternoon with peak heat index values between 102-107F. && .MARINE... Issued at 256 PM EDT Fri Aug 21 2026 A surface ridge axis remains south of the local waters through the weekend. This will maintain a period of light offshore flow, shifting south to southeast in the afternoon as the sea breeze develops. The ridge axis lifts northward on Monday, settling across the central Florida peninsula into late week. Light southerly flow becomes established across the waters from Monday onward, still turning onshore daily with the sea breeze. Seas mostly hold around 2 ft, briefly building to 3 ft offshore this weekend. Isolated to scattered offshore moving storms area forecast in the afternoons and evenings, and stronger storms will be capable of wind gusts to 34 kts or greater, frequent cloud to water lightning, and locally higher seas. && .AVIATION... (00Z TAFs) Issued at 824 PM EDT Fri Aug 21 2026 TS continue INVOF KTIX to KDAB, but should push offshore or dissipate by 03Z at the latest. Storm outflow may cause wind shifts and gusts at KMLB-KSUA through around 02Z. Some light debris SHRA ongoing inland that may linger to around 02Z, but shouldn't cause categorical impacts. After all this clears up, quiet VFR conditions will prevail overnight, with light SW-SSW winds. Winds pick up to 5-10 kts in the late morning, shifting S-SE behind the sea breeze in the afternoon as it moves inland. ISO to maybe SCT TS/SH forecast in the afternoon and evening. && .AVIATION... (18Z TAFs) Issued at 140 PM EDT Fri Aug 21 2026 Enough confidence for TS impacts at KMCO/I-4 terminals to upgrade PROB30s to TEMPOs. Kept PROB30s at KMLB-KTIX where majority of TS are forecast to develop west of the terminals, though made some timing adjustments based on latest trends and guidance. Overall TS coverage forecast to be ISO-SCT, but could become NUM along the sea breeze collision. +TSRA capable of gusts +35 kts possible, and added gusts to all TEMPOs/PROB30s. Weak SWRLY steering flow will gradually usher TS/SH NERLY and offshore, but some cells may become slow/erratic due to chaotic boundary interactions. Surface winds SWRLY 5-10 kts may become VRB at times, shifting SE-E behind a delayed/slowed ECSB in the late afternoon and evening. TS/SH push offshore dissipate after 00Z, but may linger as late as 03Z. Quiet VFR overnight after convection clears. Near identical forecast for Saturday. && .PRELIMINARY POINT TEMPS/POPS... DAB 76 94 76 92 / 20 30 20 40 MCO 76 95 76 93 / 20 20 20 60 MLB 77 94 77 93 / 30 40 30 60 VRB 75 93 75 93 / 30 40 30 50 LEE 76 93 76 91 / 20 30 30 40 SFB 76 94 76 92 / 20 20 20 50 ORL 77 95 77 93 / 20 30 20 60 FPR 76 93 75 93 / 30 40 30 50 && .MLB WATCHES/WARNINGS/ADVISORIES... FL...None. AM...None. && $$ DISCUSSION...Law AVIATION...Haley  316 FXUS61 KCTP 220035 AFDCTP Area Forecast Discussion National Weather Service State College PA 835 PM EDT Fri Aug 21 2026 .WHAT HAS CHANGED... No significant changes. && .KEY MESSAGES... 1) Trending seasonably cooler this weekend into early next week with showery periods Saturday and Sunday && .DISCUSSION... KEY MESSAGE 1: Trending seasonably cooler this weekend into early next week with showery periods Saturday and Sunday Large scale trough amplification expected over the Great Lakes region this weekend into early next week will spell a modest to seasonable cooling trend with showery periods Saturday and Sunday. The cyclonic flow may keep showers downwind of Lake Erie into Monday. Daytime highs will be near to slightly below the historical average for late August, making it feel more like mid September especially Sunday into Monday. SPC trimmed the MRGL back a bit to the west on Saturday, which should feature early day clouds and a few showers spreading from SE to NW during the day. Drier/less humid conditions are likely to prevail during the first half of next week. && .AVIATION /00Z SATURDAY THROUGH WEDNESDAY/... 00Z TAF update: Confidence in overnight fog is lower compared to last night, owing to drier air that filtered into the region during the day, along with the potential for winds to remain around 3-6 kts over the western terminals (KBFD/KJST/KAOO). Higher confidence in mist/fog/low stratus is at KLNS and to a lesser extent KMDT, where winds may be calmer overnight and a marine layer may move in from the east & increase low-level moisture/spotty shower activity. Otherwise, details from the previous discussion remain largely the same. 18Z TAF discussion: VFR will rule until some fog starts to show up in the valleys of the north-central counties. However, BFD may escape unharmed. IPT holds the highest highest probability (60%) of dropping to L/IFR in either or both fog and low clouds. Low clouds will also start to flow up into the southern tier (JST/AOO/MDT/LNS) near or even just before sunrise. SHRA may follow quickly after that. Looks like UNV/IPT/BFD should stay dry until after 18Z. But, they will also then be in the favorable air for SHRA/TSRA to form nearby. Mixing should help the cigs rise into lower-VFR (FL035) at most sites. Coverage of SHRA in the aftn/evening will expand a bit, but most SHRA/TSRA will wait until a deep trough digging over the Great Lakes will force at least one line of storms across OH and into PA. GFS is faster than NAM with this convection. But, a safe bet based on these deterministic models and multi-model ensembles of all kinds is that between 21 and 00Z they will get into Warren Co and then move eastward. The SHRA/TSRA should move east thru the night and be off to the east by sunrise. The deepening upper low then drops over the lower Great Lakes and Lower Ontario. The dryness of the airmass will likely keep convection confined to NW PA, closer to the upper cold pool and in vicinity of the moisture from LE. Monday looks similar with decent flying weather most everywhere, but a several showers will bug BFD and one or two perhaps dip toward FIG/UNV. Outlook... Sun...Restrictions possible, mainly NW in SHRA. Improvement elsewhere. Mon-Wed...Patchy morning fog, otherwise mainly VFR conditions return early next week. && .CTP WATCHES/WARNINGS/ADVISORIES... None. && $$ WHAT HAS CHANGED...Steinbugl KEY MESSAGES...Steinbugl DISCUSSION...Steinbugl AVIATION...Dangelo/Teare  233 FXUS62 KMHX 220034 AFDMHX Area Forecast Discussion National Weather Service Newport/Morehead City NC 834 PM EDT Fri Aug 21 2026 .WHAT HAS CHANGED... Heat Advisory and Severe Tstorm Watch cancelled earlier this evening A Flood Watch remains in effect for portions of eastern NC through tomorrow morning. && .KEY MESSAGES... 1) An active pattern is expected through Saturday, including a risk of strong to severe thunderstorms, heavy rain, and flooding. && .DISCUSSION... KEY MESSAGE 1...Forecast through tomorrow will be heavily dependent on various mesoscale features, which in turn will dictate where stronger storms and flooding will be focused. Fluctuation's in risk areas are likely as ongoing convective evolution is analyzed. Environment today has indeed been favorable for strong storms and torrential rainfall. Convection got an early start, developing as early as 11 AM and blossoming along the stalled frontal boundary, then compounding with convergent outflows and diurnal sound and sea breezes. Severe and flooding risk has decreased substantially for the rest of this evening, as outflows have worked over the environment bringing widespread convective inhibition to the region. Still. PWATs are impressive and moderate rainfall is occuring and expected to continue. The combination of lesser surface based instability and an anomalously moist airmass should continue to support the potential of 1-2"/hr rainfall rates. Continued rainfall chances tonight keep the Flood Watch in effect, but current radar trends suggest flooding threat is decreasing. Convective threat remains tomorrow as front remains stalled over the region. Like today, convection could get an early start as soon as 15z and spread inland through the afternoon. Shear will be quite a bit weaker and the severe threat will be less than 5%, but high forecast PWATS point to another day of efficient rainmakers and potential flooding concerns. && .AVIATION /00Z SATURDAY THROUGH WEDNESDAY/... Widespread light to moderate rain occuring, with some thunder observed along the coast. Rain chances continue through the night, with inland locales likely remaining thunder free as SBCIN has spread over the region from outflows earlier today. However, some high-res guidance is showing showers/tstorms inland as a shortwave moves through. This outcome seems to be more unlikely than not, so have kept thunder mentions out of TAF sites at this time. sub-VFR conditions (both vis and cig) are expected to set in tonight with rich low level moisture and light to calm winds. An increased TSRA risk is expected to return Saturday afternoon/evening with heavy rain, frequent lightning, and strong to severe storms possible. sub-VFR CIGs could linger through much of the day Saturday, it all depends on how much daytime heating eats away at any stratus deck overhead. Outlook: The TSRA risk should take a step down on Sunday, but the risk isn't low either. It may not be until Monday before the risk substantially lowers. && .MARINE... Local and regional observations show a frontal boundary has pushed south and stalled over area waters, orientated roughly from Ocracoke to the mouth of the Neuse River. Winds on either side of the boundary are around 10 kt with seas a subdued 2-3 feet. Main threat for marine interests through tonight and into tomorrow will be convection, especially overnight as a complex originating over SC progresses and begins to impact waters close to midnight. These storms will pose a risk of strong winds potentially exceeding 40 kt as well as waterspouts, especially for cells close to the frontal boundary. Outlook: An active thunderstorm pattern is expected to last into at least tomorrow, with a somewhat lower risk by Sunday and Monday. A more dominant southerly flow is expected to become established on Saturday and last into Sunday. A cold front then moves through late Sunday with a west to northwest wind shift. Seas build to 3-5ft on Saturday, then lay down to 2-3ft by late Sunday as winds also lay down. Light winds and reduced seas are then expected into the middle of next week. && .MHX WATCHES/WARNINGS/ADVISORIES... NC...Flood Watch until 8 AM EDT Saturday for NCZ044-079-080-090>092- 094-193-194-198. MARINE...None. && $$ DISCUSSION...RM/MS/RJ AVIATION...DAG/MS/RJ MARINE...RM/MS  337 FXUS62 KTAE 220035 AFDTAE Area Forecast Discussion National Weather Service Tallahassee FL 835 PM EDT Fri Aug 21 2026 ...New UPDATE... .KEY MESSAGES... Issued at 835 PM EDT Fri Aug 21 2026 - Daily chances for thunderstorms remain in the forecast. Some strong to severe storms are possible this afternoon and evening. Strong wind gusts of 40-60 mph, frequent lightning, and locally heavy rainfall are expected with the stronger storms that develop. - The heat wave is poised to finally break with a more typical summertime pattern returning early next week. && .UPDATE... Issued at 835 PM EDT Fri Aug 21 2026 Forecast is generally on track this evening. No major updates were required. && .SHORT TERM... (This Evening through Saturday) Issued at 220 PM EDT Fri Aug 21 2026 For the rest of this afternoon, a remnant MCV will slowly spin down over southeast Georgia just east of Lanier and Lowndes Counties. We'll be watching a shortwave moving southward around the ridge to our west, which will precede the larger trough over the Great Lakes that will move through on Saturday. This shortwave will help generate scattered to numerous showers and storms later this afternoon continuing into the evening hours. Some of this convection could become more organized into clusters or lines. DCAPE and instability should increase further into the afternoon hours, which will lead to a threat of strong downbursts. Also, low to mid-level lapse rates will steepen with cooler temperatures moving in aloft, which could lead to a threat of some hail. SPC has maintained the Marginal Risk of severe weather (level 1 of 5) for this afternoon and evening for most of the area. Some of the guidance during the overnight hours has outflow from storms to our northwest moving into our area, which may help spark isolated to scattered showers and storms late tonight. Lows will be in the low to mid 70s. For Saturday, the shortwave moves more into our area, bisecting our area from northeast to southwest. So, rain chances will be more confined to areas from Panama City to Valdosta southward. While soundings aren't quite as impressive tomorrow, still a gusty wind and maybe small hail threat exist. Currently, there is no severe weather risk outlined for tomorrow from SPC. Drier air will sneak into our area as well, which should keep us below Heat Advisory levels for Saturday. If this holds, it would be the first day without a Heat Advisory in our area since August 10th. It will still be hot with highs in the lower half of the 90s with heat index values of 102-107. && .LONG TERM... (Saturday night through next Thursday) Issued at 220 PM EDT Fri Aug 21 2026 Sunday and Monday will be the driest days with PWATs crashing to 1.2 to 1.5 inches. Thus, little coverage of showers and storms is expected Sunday and would occur mainly near the sea breeze. Monday, however, we'll have to watch if a shortwave rounds the ridge to our west and enters our area during the afternoon, which may help spark better coverage of showers and storms. The drier air will make it feel much more tolerable (until the sea breeze arrives). Highs will still be in the mid to upper 90s both days, but heat index values will only manage the upper 90s to 105 in most spots. Through much of the upcoming week, the ridge will remain off to our west, and we'll remain in northwesterly flow aloft. So, we'll continue to monitor for any ridge-riding disturbances, but our rain chances will gradually increase with a return to a summer pattern. Highs remain in the low to mid 90s with heat index values of 102-108. && .AVIATION... (00Z TAFS) Issued at 723 PM EDT Fri Aug 21 2026 A broken line of thunderstorms are and will be affecting all terminals this evening. The ABY terminal will see light to moderate rain for the next few hours. The DHN, VLD, and TLH terminals will see ongoing thunderstorms with gusty winds and frequent lightning, as noted in prevailing FROM groups and TEMPO groups. A few storms may reach down to ECP later tonight, as shown in a PROB30 group. After these storms clear tonight, VFR cigs are expected to prevail. Showers and thunderstorms return tomorrow afternoon for all TAF sites. && .MARINE... Issued at 305 PM EDT Fri Aug 21 2026 Scattered storms are expected through Saturday, mainly in the overnight and morning hours. However, clusters of storms could move into the waters during the evening hours from land. Gusty winds and brief waterspouts are possible in the stronger storms. Otherwise, mainly gentle to occasionally moderate southwesterly breezes will continue over the next several days with seas around 1-2 feet. && .FIRE WEATHER... Issued at 220 PM EDT Fri Aug 21 2026 Generally light west to southwest transport winds will continue through Saturday, then more variable on Monday. Dispersions will remain good overall each afternoon. Scattered showers and storms are expected again Saturday afternoon, but decreasing coverage is anticipated both Sunday and Monday. Gusty, erratic winds and dangerous lightning strikes will be possible. Drier air will move in over the weekend, but RH values will stay above critical levels. && .HYDROLOGY... Issued at 220 PM EDT Fri Aug 21 2026 Thunderstorms could produce locally heavy rainfall today and Saturday. If the storms are slow-moving, they could produce several inches of rain in a short period of time. This would lead to some nuisance to isolated flash flood concerns, particularly is low-lying or poor drainage areas. && .SPOTTER INFORMATION STATEMENT... Spotter activation is not requested. However, spotters are always encouraged to safely report significant weather conditions when they occur by calling the office or tweeting us @NWSTallahassee. && .PRELIMINARY POINT TEMPS/POPS... Tallahassee 74 93 74 97 / 30 70 0 10 Panama City 77 90 78 93 / 40 50 10 10 Dothan 73 94 73 96 / 40 10 0 10 Albany 73 95 73 97 / 50 20 0 0 Valdosta 73 94 73 97 / 50 60 0 10 Cross City 75 91 74 93 / 20 70 40 40 Apalachicola 78 89 78 92 / 40 60 20 20 && .TAE WATCHES/WARNINGS/ADVISORIES... FL...None. GA...None. AL...None. GM...None. && $$ SHORT TERM...Young LONG TERM....Young AVIATION...Montgomery MARINE...Young FIRE WEATHER...Young HYDROLOGY...Young  320 FXUS65 KSLC 220035 AFDSLC Area Forecast Discussion National Weather Service Salt Lake City UT 635 PM MDT Fri Aug 21 2026 .KEY MESSAGES, Issued 1018 PM MDT Thu Aug 20 2026... - Hot temperatures will persist over the valleys of northern Utah Friday, with low temperatures in the mid to upper 70s providing little overnight recovery. - Monsoonal moisture will surge into Utah and southwest Wyoming Friday and Saturday, bringing an increased threat of thunderstorms producing heavy rainfall and flash flooding. - Moisture is expected to decrease from Sunday through Tuesday, bringing less coverage of showers and thunderstorms and lower potential for heavy rainfall early next week and beyond. && .DISCUSSION, Issued 145 PM MDT Fri Aug 21 2026... Late morning and afternoon satellite imagery reveals a broad veil of cloud cover moving across central and northern Utah with far southern and eastern Utah remaining largely cloud free. Within this area of enhanced cloud cover, isolated thunderstorms are developing, owing to the increased atmospheric moisture and instability building into the region. For the northern and central portions of the forecast area, shower and thunderstorm coverage is expected to increase through the afternoon as the shortwave leading the influx of moisture continues north. The subsident wake of this wave, however, is likely to limit the amount of convection and storm development that we see across the southern area. This is the biggest change with the forecast today. As such, while thunderstorms producing heavy rainfall and increased flash flood potential are still expected in southern Utah, the coverage of such will be much less than previously forecast. This threat is now transitioning into central Utah, as well as a portion of northern Utah. In northwest Utah where sufficient surface moisture is lacking, any storms developing will carry potential for strong outflow winds in excess of 40 mph. This wave of energy will exit the region through Saturday, placing much of the forecast area under a subsident wake. While atmospheric moisture will be elevated, the areawide subsidence will help to inhibit widespread shower and thunderstorm coverage. Again, while coverage is not expected to be as widespread as previously thought, any storms that do develop will carry higher than normal potential of heavy rainfall. If these storms end up over a particularly sensitive area (slot canyons, recent burn scars, urbanized areas, etc.) then the threat of flash flooding will be elevated. The increase in areawide moisture will help to moderate temperatures as we head through the weekend, with most areas outside of lower Washington County expected to fall below triple digit territory. Models have been consistent with the support of a drying atmosphere from Sunday forward, which will allow for lower coverage of showers and thunderstorms across Utah and southwest Wyoming, as well as a decreasing risk of flash flooding into early next week. Dry conditions look to be maintained from roughly Wednesday forward as moisture vacates the region and high pressure remains in place. && .AVIATION... KSLC...The SLC terminal will see VFR conditions through the night with cigs expected to stay above 6000 ft AGL. There is a 20-30 percent chance of additional development of showers and thunderstorms during the late evening into the early part of the overnight hours, which could produce gusty and erratic winds. Variable but prevailing northeasterly winds are expected to shift to the south between 02Z and 04Z. The northerly wind shift tomorrow is expected to occur between 19Z and 21Z, with a low (20-30) percent chance of additional showers and thunderstorms impacting the terminal during the afternoon and early evening. REST OF UTAH AND SOUTHWEST WYOMING...VFR conditions are expected across the airspace through the overnight hours. Scattered showers and thunderstorms over the northern two-thirds of the state are expected to become increasingly focused over northern portions of the area late evening and into the early overnight hours before weakening. With monsoon moisture in place, scattered showers and thunderstorms will again develop tomorrow. Any of these storms will be capable of bringing lightning, brief mountain obscurations, and brief MVFR conditions in heavier rainfall. && .FIRE WEATHER, Issued 145 PM MDT Fri Aug 21 2026... Hot temperatures remain in place across the area today, with dry conditions expected in northwest and eastern Utah while southwest Utah sees an increase in moisture. With the increase in moisture across the southern half of Utah, afternoon shower and thunderstorm development is expected through the remainder of today with storms bringing potential for wetting rains. Coverage of showers and thunderstorms will be greatest across central and northern Utah, however, wetting rain potential will decrease north of the US-50/ I-70 corridor. The bigger threat for central and northern Utah will be isolated dry lightning and gusty outflow winds in excess of 35-40 mph. These strong winds and dry surface conditions may bring short-lived critical fire weather conditions. Moisture will continue to push northward on Saturday, bringing improvement to afternoon humidity across the northern and central area while the southern area will see the beginning of a slow drying trend. That said, shower and thunderstorm potential will still be elevated over the high terrain features throughout Utah over the weekend, however, the chances for wetting rains will sharply decrease. Moisture will gradually decrease areawide each day from Sunday through Tuesday next week, with decreasing coverage of precipitation expected alongside a drying surface humidity trend. By Wednesday, widespread humidity at, or below, 15 percent is anticipated to be maintained through the remainder of the week. && .SLC WATCHES/WARNINGS/ADVISORIES... UT...Heat Advisory until 7 AM MDT Saturday for UTZ101>106. WY...None. && $$ PUBLIC...Webber AVIATION...Traphagan FIRE WEATHER...Webber For more information from NOAA's National Weather Service visit... http://weather.gov/saltlakecity  852 FXZS60 NSTU 220045 AFDPPG Area Forecast Discussion National Weather Service Pago Pago AS 145 PM SST Fri Aug 21 2026 .Discussion...Moderate to breezy southeast trade winds with embedded showers will dominate weather conditions across American Samoa through the weekend and into next week. A strong high near New Zealand continues to build and drift east, keeping the trade- wind regime in place. Latest model guidance suggests the high will weaken midweek as it becomes centered southeast of the islands, allowing winds to trend more easterly. A trough will also develop nearby, increasing instability and enhance shower coverage. With this update, the main adjustment to the previous forecast will be towards the latter part of the new week, to account for the trough-related weather. && .Marine...Latest PacIOOS wave-buoy observations remain within advisory thresholds. Combined southeast trades and a south swell continue to produce hazardous coastal conditions. A High Surf and Small Craft Advisories remain in effect as these hazardous conditions are expected to last through the weekend and into early next week. && .PPG WATCHES/WARNINGS/ADVISORIES... High Surf Advisory Small Craft Advisory && $$  110 FXUS64 KHUN 220051 AFDHUN Area Forecast Discussion National Weather Service Huntsville AL 751 PM CDT Fri Aug 21 2026 ...New NEAR TERM, SHORT TERM, LONG TERM... .KEY MESSAGES... Updated at 751 PM CDT Fri Aug 21 2026 - There is a low to medium chance of patchy dense fog late tonight into early Saturday morning. - There are low to medium chances of thunderstorms next week. However, timing and impact confidence remains low at this time. && .NEAR TERM... (Tonight through Saturday Night) Issued at 751 PM CDT Fri Aug 21 2026 A cold front has shifted south of the TN valley in central MS, AL and GA. A secondary trough axis extends northeast a weak low in central AL through northwest GA and eastern TN where a couple of thunderstorms and showers had developed earlier. At this point, it appears like a dry overnight is expected with the loss of heating along this trough axis. Northerly flow has dropped dew points into the upper 60s to lower 70s this evening over northwest and north central AL into southern middle TN. PW values are dropping into the 1-1.25 inch range as well. Patchy fog is expected to develop as the boundary layer decouples and with a mostly clear sky. Overnight lows will dip into the middle to upper 60s. Another cold front was dropping south through the eastern Corn Belt into the lower MO valley. This front will drop into TN and AR Saturday afternoon and through north AL during the evening hours. MCS clusters are forecast tonight in the Plains which drop southeast into OK and AR in some fashion on Saturday. The NBM PoPs remain quite low, with slightly higher PoPs in our western counties (but still 20% or less). We will monitor trends with the new model runs later tonight, but expect only minor adjustments if any. Forecast highs on Saturday are in the lower 90s for valley areas, and upper 80s atop the higher plateau locations with dew points in the middle 60s which will feel much more comfortable. Any thunderstorm activity should either dissipate or shift south of the TN valley by late Saturday night. && .SHORT TERM... (Sunday through Monday) Issued at 751 PM CDT Fri Aug 21 2026 Dry weather with seasonal temperatures are foreseen on Sunday with highs in the upper 80s to around 90 as high pressure builds south from the Upper Midwest into the OH and TN valleys. Overnight lows will be on the cool side with lower to middle 60s. NW flow at 5h will persist into Monday, with a low to mid level Theta-E gradient and convergence zone located across IA through MO and AR. This will be the genesis region of clusters of showers and thunderstorms which will likely be elevated/higher based as they reach our area on Monday, when we have low chances in the forecast. && .LONG TERM... (Monday night through Friday) Issued at 751 PM CDT Fri Aug 21 2026 In the extended forecast, we will get a break from the extreme heat conditions, however in exchange for that, we will be stuck in an unsettled pattern. We will start off with the pattern of an upper level low up in Quebec and the far NE U.S with an amplified ridge stretching from the southern Rockies up through the Northern Plains. On the back side of the ridge, a smaller upper-level low in Manitoba will try to be the driving force for a pattern change. As that smaller low slides SE into the Upper Great Lakes mid-week, the ridge will be dampened enough for it to round the ridge. This pattern will keep us in a northwesterly flow through the week. Embedded in this flow will be shortwaves that will swing through the TN Valley, keeping daily rain chances in. Right now it looks like there is a chance for an MCS to drop through on Tuesday, then again Wednesday night into Thursday morning. Will keep an eye on trends for specific hazards and timing, but for now will stick with NBM POPs. Daytime highs will be in the upper 80s to lower 90s with overnight lows around 70 degrees. && .AVIATION... (00Z TAFS) Issued at 534 PM CDT Fri Aug 21 2026 Patchy fog is forecast to develop by 07-08Z, with a medium chance of MVFR conditions and low chance of IFR conditions due to lowered visibility. VFR conditions will return by 13Z for the balance of the period with a light north-northwest wind. && .HUN WATCHES/WARNINGS/ADVISORIES... AL...None. TN...None. && $$ NEAR TERM...17 SHORT TERM....17 LONG TERM....JMS AVIATION...17  212 FXUS63 KABR 220054 AAB AFDABR Area Forecast Discussion...UPDATED National Weather Service Aberdeen SD 754 PM CDT Fri Aug 21 2026 .KEY MESSAGES... - Mainly dry conditions will continue through next Wednesday with temperatures around average for this time of year. - There is a 30-60% chance for showers and thunderstorms during the day Sunday into early Sunday evening over central SD, expanding to northeastern SD/west central MN Sunday night while increasing to a 40-70% chance. - There is a Marginal Risk (level 1 out of 5) of severe weather Sunday night over much of central to northeastern SD. Brief heavy rain, lighting, and strong winds to around 60 mph will be the main concern. && .UPDATE... Issued at 740 PM CDT Fri Aug 21 2026 The showers with some embedded thunder has cleared the southeast corner of the CWA. Looks like the only remaining mid-level short-wave in northwest flow is heading into northwestern/central MN. While the PVA side of this wave can continue to influence forcing/lift over the far northeast corner of the CWA, there could be a shower or two straifing Roberts/Big Stone/Traverse counties from now through ~05Z. Otherwise, the rest of tonight should be dry with surface high pressure still building down over the region. No changes to the tonight period forecast. UPDATE Issued at 626 PM CDT Fri Aug 21 2026 See below for an aviation forecast discussion for the 00Z TAFs. && .DISCUSSION... Issued at 245 PM CDT Fri Aug 21 2026 Small waves in our otherwise northwesterly flow at 500mb is helping support clouds and light showers or sprinkles mainly southwest and north of the forecast area this afternoon. The last of any lingering light showers should be to our east by 02Z. Otherwise, mainly dry weather continues through 05Z Sunday. The 500mb ridge set up to our west looks to push overhead Sunday, as a surface trough strengthens over western SD/NE. This will bring our next chance of precipitation, with a 30-60% chance of showers and a slight chance of thunderstorms over mainly central SD Sunday into early Sunday evening before expanding/pushing over northeastern SD and west central MN Sunday night while increasing to 40-70%. As noted in the previous discussion, with high PW values, heavy rain will be possible. There is a Marginal Risk (level 1 out of 5) of severe weather Sunday night over much of central to northeastern SD. Brief heavy rain, lighting, and strong winds to around 60 mph will be the main concern if storms develop. We'll keep an eye on Monday night into Tuesday as well as the 500mb Canadian low rotates through south central Canada with a stacked surface low pushing a cold front across our area. Additional showers or storms will be possible. Otherwise, we'll be looking at Thursday afternoon and evening for another round of showers or thunderstorms. Upper 70s to mid 80s will remain common through the period, with the highest temperatures Monday over central SD (a few low 90s possible Monday or Tuesday of next week. && .AVIATION /00Z TAFS THROUGH 00Z SUNDAY/... Issued at 626 PM CDT Fri Aug 21 2026 Terminals KABR,KATY,KPIR,KMBG There's a rain shower working over KATY right now. Maybe a brief stint of MVFR visby there between 00Z and 01Z. Otherwise, dry VFR conditions are forecast through Saturday afternoon. && .ABR WATCHES/WARNINGS/ADVISORIES... SD...None. MN...None. && $$ UPDATE...10 DISCUSSION...06 AVIATION...10  452 FXHW60 PHFO 220059 AFDHFO Area Forecast Discussion National Weather Service Honolulu HI 259 PM HST Fri Aug 21 2026 .SYNOPSIS... Strong trades develop this weekend as a tropical system delivers heavy rainfall to windward and southeast slopes of the Big Island. A Flood Watch remains in effect for the Big Island. && .DISCUSSION... Trade winds remain light over the western end of the state as surface troughing continues lifting off to the northwest. This trough, the remnant of TC Hernan, has draped a modest band of moisture over Oahu this afternoon where sea breeze convergence has capitalized on the resident weakly stable environment and led to numerous showers over the interior. Prospects for afternoon showers on the other islands remain limited due to diminished moisture and/or stronger trade winds. Attention then turns to Tropical Storm Moke which is currently positioned about 650 miles southeast of Hilo and is lifting slowly NW. Satellite presentation is characteristic of a storm affected by southerly shear with convection concentrated north of the center of circulation. Moke is also drawing north a band of rich moisture originating from the deep tropics. PWAT values within this moisture plume average about 2.5" which is what it will be when it reaches the Big Island late Saturday night into Sunday. The forecast quandary for today is seemingly answered by a northward jump in the 18z GFS to much more closely match the 12z EC and the official NHC forecast. This in turn adds confidence to the official forecast which was based on the latter 2 sources and is considerably wetter for the Ka'u and Puna Districts of the Big Island. Instead of straight trades through the lowest 10kft or so as suggested by this morning's GFS, the northern periphery of the envelope of cyclonic flow will envelop the Big Island allowing winds to veer to SE and steer greater moisture content to the SE facing slopes of the Big Island. The forecast for around 10" in this area, locally higher, remains on track. Rain will begin over SE and Windward Big Island late Saturday night or early Sunday morning, peak in intensity Sunday afternoon/evening and then linger through Monday, particularly over upslope areas where afternoon convection may be fairly robust on Monday afternoon. Strong trades ensure fast-moving showers elsewhere except perhaps Windward Maui where a few inches of rainfall appears increasingly likely. Though trades may be on the wetter side on Monday, prospects for flooding for Molokai, Oahu, and Kauai appear quite limited. The Flood Watch for the Big Island remains in good shape with no adjustments needed. Secondary forecast concern is wind magnitude. As with the rainfall forecast, the northward jump by the 18z GFS increases confidence in the existing wind forecast. The pressure gradient north of TS Moke will begin strengthening tonight with peak winds expected Sunday and Sunday evening. Low stability and plenty of moisture advection will make for inefficient and limited downsloping. Although the usual suspects will be windy, will shy away from a High Wind Watch for any zones at this time. Instead, this appears to be a solid Wind Advisory (gusts to 50 mph) for at least Maui County and the Big Island and possibly Oahu as well. Low amplitude high pressure remains anchored along 30N supporting breezy trades continuing through most or all of next week. && .AVIATION... A surface trough has moved north of Kauai, however light winds remain over the western islands, leading to local land and sea breezes. Clouds and showers formed over the interior of Oahu this afternoon prompting AIRMET SIERRA for mountain obscuration. Anticipate these clouds and showers to dissipate shortly after sunset. Behind the trough, trades are starting to fill back in, and will gradually strengthen across the island chain from east to west. Trade winds will continue to strengthen on Saturday and AIRMET TANGO will likely need to be issued for low level turbulence. Addtional pockets of MVFR conditions are possible with passing clouds and showers outside of those on Oahu this afternoon. Otherwise, VFR conditions are expected to prevail. && .MARINE... A trough in the northwest offshore waters will continue to move northwest as trade winds have begun to fill in across the coastal waters from east to west. A Small Craft Advisory (SCA) has been issued through Saturday afternoon for the windier waters and channels around Maui County and the Big Island. As trade winds continue to strengthen over the weekend as Tropical Storm Moke passes south of the state, the SCA may need to be expanded starting Saturday night through Sunday. Although seas greater than 10 feet will most likely be over the eastern half of the coastal waters. Across the offshore waters, a Tropical Storm warning as been issued as Tropical Storm conditions are expected Saturday night into Sunday across the southern offshore waters. Surf along south facing shores will remain elevated through the weekend. Another reinforcing swell is expected over the weekend which should boost surf heights near the summer average over the weekend. A series of south swells are expected next week with above average surf likely during the second half of next week potentially up to High Surf Advisory levels. Surf along east-facing shores remains below average tonight then is expected to build this weekend as the trades restrengthen. Surf along east and south- facing shores will be compounded by a southeast swell generated by Tropical Storm Moke that will build through Sunday and then become south, then southwest through early next week. This short- period tropical swell could cause surf to approach advisory levels along east facing shores of the Big Island Saturday night into Sunday, though forecast confidence is on the lower side as the wind field with this tropical cyclone is expected to be relatively small and the forecast track may shift slightly. North facing shores will remain tiny through tonight with a small medium to long period west north swell from Hurricane Lala this weekend. && .FIRE WEATHER... Trade winds increase over the weekend and the inversion, currently around 6-7kft, will steadily weaken and eventually erode altogether as deep moisture associated with TS Moke moves into the area late Saturday night into Sunday. Heavy rain is expected over windward and SE facing slopes of the Big Island on Sunday. && .HFO WATCHES/WARNINGS/ADVISORIES... Flood Watch from late Saturday night through Monday afternoon for Big Island- Small Craft Advisory until 6 PM HST Saturday for Maalaea Bay- Pailolo Channel-Alenuihaha Channel-Big Island Leeward Waters-Big Island Southeast Waters. && $$ DISCUSSION...JVC AVIATION...M Ballard MARINE...Shigesato FIRE WEATHER...JVC