692 FXUS65 KPSR 222109 AFDPSR Area Forecast Discussion National Weather Service Phoenix AZ 209 PM MST Sat Aug 22 2026 .KEY MESSAGES... - High temperatures reach or exceed 110 degrees nearly every day through the next week and will be near daily records, while morning lows remain unusually warm. - Extreme Heat Warnings are in effect through next Saturday evening with daily Major to Extreme HeatRisk. - Afternoon and evening strong to locally severe thunderstorms will primarily favor higher terrain areas through the start of next week, with drier and less favorable conditions next week. && .SHORT TERM /TODAY THROUGH MONDAY/... Extreme heat will be the primary weather hazard through the short and long term forecast with very strong high pressure persisting over the region. Latest objective analysis still shows a 599dam anticyclone centered over northern NM, with H5 heights around 595-597dam over the local area. These magnitudes are at or above the 99th percentile of climatology. This will continue leading to well above normal high and low temperatures through this weekend. A drying and warming of the PBL was observed over the last 24 hours, as seen in observed soundings. This should result in high temperatures this afternoon 1-3 degrees warmer than yesterday, with lower deserts topping out around 112-116 degrees. A slight weakening of the subtropical high, and repositioning to eastern NM, Sunday into Monday will support a slight cooling of temperatures through Monday. Potentially more active showers and storms Sunday evening/night in south-central AZ may add a bit to the cooling into Monday. Latest NBM forecast highs for Sunday are around 108-114 degrees and then 106-112 degrees for Monday. Morning low temperatures will remain very warm, up to 5-10 degrees above normal, in the mid 80s to around 90 degrees across the lower deserts. The unusually hot temperatures will lead to widespread Major HeatRisk today and Sunday, with a decrease in coverage of Major HeatRisk for Monday. An Extreme Heat Warning remains in effect through this weekend. Afternoon thunderstorms today should mostly favor the same areas as yesterday, but with the drying of the PBL, surface-based instability will be lower today. Mean mixing ratios are down 8 g/kg or lower and surface dew points at midday were mostly around 50-55 degrees. Lower instability means overall less intense updraft strength. This does not mean storms that develop cannot still become strong to severe. With the high T-Td spreads and high LCLs, DCAPE remains quite high (>1500 J/kg), which will promote strong to locally severe downbursts. Latest hi-res models favor isolated storms developing mostly along the mountains east of Phoenix and over terrain features south of Phoenix, with a focus mostly in central Pima County and portions of southern Maricopa and western Pinal counties. The storms to the south will be capable of sending dusty outflows northward heading into the evening, along with debris clouds and perhaps some weak showers or virga. Just like yesterday, the odds of an outflow popping off storms closer to or in Phoenix are low (5-10%), but it is still not impossible for 1-2 strong to severe storms to pop up with the right amount of forcing. Some ACCAS showers also cannot be ruled out across south-central AZ heading into Sunday morning within some of the debris clouds moving across the area. For Sunday, models continue to support a strong moisture return, albeit brief, in the evening and overnight hours. There are indications that instability will increase again south and southwest of Phoenix with storms again developing in similar locations with similar potential for strong to locally severe wind gusts. Then heading into the evening and overnight hours it looks like there will be a strong gulf surge as well as indications of perhaps a subtle shortwave/vort max moving up out of Sonora. This may increase storm survivability into the Phoenix area. NBM PoPs remain quite low despite this. The 12Z HREF shows a 30% neighborhood probability for dBZ>40 in south-central AZ, including Phoenix, Sunday evening/night. So, PoPs were increased slightly to at least show a slight chance (10-20%) across south-central AZ. Isolated storms are again forecast over higher terrain features for Monday afternoon and evening, but there may be stronger storms and greater coverage over some of the features west of Phoenix, like the Kofas to Harcuvar Mtns and portions of eastern Riverside County following the moisture increase the night before. && .LONG TERM /TUESDAY THROUGH NEXT FRIDAY/... Ensemble members are in good agreement that by Tuesday drier air will start to filter back into the region as the subtropical high restrengthens and starts to retrograde westward back to over our region. By the middle of the week the center of the high will be straddling the AZ/NM border and by the end of the week the center of the high is forecast to be over AZ. As the high moves overhead, PWATs are shown to drop into a 0.9-1.2" range across our region and with warmer temperatures aloft and subsidence chances for thunderstorms will be poor across the region. The NBM shows that Tuesday and Wednesday there could be enough moisture around to support isolated thunderstorm chances for the higher terrain areas. But by the end of next week thunderstorm chances for our area shut off and will mainly be relegated to the Mogollon Rim. Unusually hot temperatures will be the main story next week. As mentioned above the subtropical high will slowly retrograde back over our region beginning on Tuesday, which will result in a quick warming trend for our area. The high is also expected to strengthen to around 596-598dam during this time. The combination of the center settling over our region and strengthening will result in temperatures heating up to around 10 degrees above normal for this time of year. Afternoon highs (morning lows) are forecasted to be in the 112-118 (85-93) degree range across the lower deserts and in the 102-112 (75-85) degree range across the higher terrain areas. There is a good chance daily record highs and warm lows will be tied or broken and temperatures may even near monthly records. The increase in temperatures will also result in an increase in coverage of Major HeatRisk, back to widespread beginning Tuesday and then widespread Extreme HeatRisk by Thursday. Confidence in the heat forecast for next week remains high. So, the Extreme Heat Warning will continue through the workweek and has now been extended through Saturday, in collaboration with the Tucson office. The warning will likely be expanded to our entire CWA by the middle of the week with the development of widespread Extreme HeatRisk. && .AVIATION...Updated at 1735Z. South Central Arizona including KPHX, KIWA, KSDL, and KDVT: Uncertainty in TSRA/SHRA coverage and corresponding gusty outflow winds/wind shifts will be the primary forecast challenge through Sunday afternoon under periods of mid/high cloud decks. Confidence is good that light E/SE or VRB winds will slowly transition to W/SW by mid to late afternoon. TS development over higher terrain areas may send gusty outflow winds towards the Phoenix terminals during the late afternoon/early evening. Current Hi-Res guidance shows the best coverage of showers and storms will be over Southwestern Pinal County, which would make a southerly outflow the most likely/predominant favored direction. While direct TS impacts are not likely at the terminals, briefly gusty winds and decaying SHRA could affect operations early-mid evening. If more concentrated storms can materialize along with multiple colliding outflow boundaries, better chances for isolated TS development in lower elevations will be enhanced with stronger and more prolonged wind gusts. Southeast California/Southwest Arizona including KIPL and KBLH: No major weather issues will exist through Sunday morning under mostly clear skies. Trends in winds should be similar to the past 24 hours, generally varying between SE and SW with extended periods of nearly calm conditions in between. TS activity over the Baja spine late this afternoon may send an outflow and decaying SHRA towards KIPL prior to sunset. Chances for direct TSRA impacts are too low to include in the TAF, however gusty SW winds justify a continued mention through the early evening. && .FIRE WEATHER... Hot and seasonally dry conditions are expected nearly every day, through next week. Aside from a brief increase in moisture Sunday- Monday, minimum RH values each afternoon will be around 12-18% (15- 25% Sun-Mon). Temperatures will be around 5-10 degrees above normal through the next week, with lower desert highs eclipsing 110 degrees nearly every afternoon. There will be slight chances for storms each afternoon through Monday, but they will mostly favor the higher terrain areas. Drier conditions, with lower storm chances are expected by the middle of next week. Outside of thunderstorm outflow winds, winds will follow the typical diurnal tendencies with some modest afternoon upslope gustiness. && .CLIMATE... Record highs: Date Phoenix Yuma El Centro ---- ------- ---- --------- Aug 22 113 in 2011 115 in 1969 117 in 1969 Aug 23 114 in 2011 115 in 2011 116 in 1969 Aug 24 115 in 2020 119 in 1985 117 in 1985 Aug 25 113 in 2011 116 in 1962 117 in 1962 Aug 26 117 in 2011 115 in 2020 115 in 1981 Aug 27 114 in 2023 120 in 1981 117 in 1981 Aug 28 117 in 2023 118 in 2023 117 in 2009 && .PSR WATCHES/WARNINGS/ADVISORIES... AZ...Extreme Heat Warning until 8 PM MST Saturday for AZZ530>555-559- 560. CA...Extreme Heat Warning until 8 PM PDT Saturday for CAZ562-565>567- 569-570. && $$ SHORT TERM...Benedict LONG TERM...Berislavich/Benedict AVIATION...Whittock/18 FIRE WEATHER...Berislavich/Benedict CLIMATE...18  422 FXUS61 KRLX 222117 AFDRLX Area Forecast Discussion National Weather Service Charleston WV 517 PM EDT Sat Aug 22 2026 .WHAT HAS CHANGED... 514 PM Update... Expanded the Severe Thunderstorm Watch to cover portions of southern West Virginia and our northeastern Kentucky counties. 158 PM Update... A Severe Thunderstorm Watch has been issued for portions of southeast Ohio and northern West Virginia this afternoon for storms capable of producing damaging wind gusts and hail. && .KEY MESSAGES... 1) Severe weather potential grows in earnest this afternoon and evening ahead of a cold front. Storms will be capable of produce damaging winds, hail, and heavy downpours that may lead to flash flooding. 2) In the wake of the front, a stretch of dry weather settles into the region alongside a brief cool down in temperatures. && .DISCUSSION... KEY MESSAGE 1... 514 PM Update... The severe thunderstorm watch that goes until 9 PM tonight has been expanded to include portions of southern WV and all of northeastern KY. This is a conditional risk as previous rounds of storms have weakened instability some across the area. HRRR and RAP still show pockets of 2,500 to 3,500 CAPE across the area in locations where storms have not moved through yet. These will be areas to watch for pop up strong to severe thunderstorms as another round is projected to move through this afternoon and evening. 158 PM Update... Earnest shower and thunderstorm development is underway across the Ohio River Valley out ahead of a cold front slated to pass overhead tonight into Sunday morning. An unstable airmass preceding the front has yielded optimal conditions for cumulus to quickly develop further into scattered showers and storms. With destabilization quickly arising, a Severe Thunderstorm Watch has been issued in collaboration with the Storm Prediction Center and neighboring offices. This Watch currently encompasses portions of southeast Ohio and north-central West Virginia, where severe weather may be observed within the next few hours. Additional expansion of the Watch is not out of the question for the southern half of the forecast area, but will continue to monitor the evolution of storms to determine how the rest of the afternoon and evening will shake out. Storms preceding the front today will be capable of producing damaging wind gusts, hail, and heavy downpours that may lead to flash flooding. While some soil recovery has occurred in locations who recently faced a multitude of days featuring flooding, additional rainfall could invigorate further hydro impacts across the region. Storms will be progressive in nature, which should help to alleviate a response from instantaneous rainfall rates, but locations would then be susceptible to any training effects that may set up through the course of the evening. Convection marches into the post-sunset timeframe, but will gradually diminish with the progression of the front overnight. Precipitation will then bank up along the northeast WV mountains by early Sunday morning and wrap up altogether by daybreak once the front has completed its passage through the mountains. KEY MESSAGE 2... In the wake of the cold front, Sunday will feature the start of dry weather that stretches into the start of next week. High pressure settling into the Ohio Valley will yield a push of dry air, alongside much cooler temperatures. Daytime highs will span the 60s along the mountains and 70s to low 80s in the lower elevations, while overnight conditions will feature low temperatures tumbling down into the 50s and 60s. Next opportunity for precipitation arrives for the second half of the work week, when a warming trend instigates diurnally driven showers and storms over the Central Appalachians. && .AVIATION /21Z SATURDAY THROUGH THURSDAY/... Shower and thunderstorm development is underway across our airspace this afternoon ahead of a cold frontal passage. Storms today are capable of producing damaging winds, hail, and heavy downpours. Opted for tempo groups at all sites advertising an uptick in winds and lowered visibilities in the event a storm passes over the airfield. Convection is progged to last through the evening into late tonight, so carried a mention of thunder that spills into the new Zulu day across the board. The front itself is expected to slide through the Central Appalachians overnight tonight, with lingering showers banking up along the higher terrain. The presence of the boundary and excessive moisture will stir up another round of fog and low level stratus for much of the region overnight into Sunday morning. Once fog erosion transpires after sunrise, the rest of the TAF period will branch back out into VFR conditions and kick off a period of dry weather for the start of the new week. FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 18Z SUNDAY... FORECAST CONFIDENCE: Low to Medium. ALTERNATE SCENARIOS: Timing and intensity of storms may vary from the forecast through tonight. Restrictions from fog and low stratus may vary this overnight into Sunday morning. EXPERIMENTAL TABLE OF FLIGHT CATEGORY OBJECTIVELY SHOWS CONSISTENCY OF WFO FORECAST TO AVAILABLE MODEL INFORMATION: H = HIGH: TAF CONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL. M = MEDIUM: TAF HAS VARYING LEVEL OF CONSISTENCY WITH MODELS. L = LOW: TAF INCONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL. UTC 1HRLY 19 20 21 22 23 00 01 02 03 04 05 06 EDT 1HRLY 15 16 17 18 19 20 21 22 23 00 01 02 CRW CONSISTENCY H H H H H H H H H H L M HTS CONSISTENCY H H H H H H H H H H H H BKW CONSISTENCY H H H H H H H H H H H M EKN CONSISTENCY H H H H H H H H H H L M PKB CONSISTENCY H H H H H H H H H H M H CKB CONSISTENCY H H H H H H H H H H M M AFTER 18Z SUNDAY... IFR conditions possible in low stratus and fog Monday morning. && .RLX WATCHES/WARNINGS/ADVISORIES... WV...None. OH...None. KY...None. VA...None. && $$ DISCUSSION...05/LTC AVIATION...05  611 FXUS66 KLOX 222121 AFDLOX Area Forecast Discussion National Weather Service Los Angeles/Oxnard CA 221 PM PDT Sat Aug 22 2026 .SYNOPSIS...22/106 PM. Minimal changes expected through the weekend with above normal temperatures. Patchy night and morning low clouds and fog will be confined to coastal areas, mostly north of Point Conception. Additional warming is expected next week with periods of extreme heat in some areas, especially starting Tuesday. && .SHORT TERM (TDY-TUE)...22/221 PM. The heat is on. It looks to be a very hot week across southwest California, especially Tuesday and beyond as high pressure aloft builds in from the east onshore gradients start to relax and possibly even turn lightly offshore. Temperatures today are similar or slightly cooler than the last couple days but models are indicating weakening onshore flow this week, especially starting Tuesday while at the same time heights and thicknesses rise due to high pressure building from the heat. In addition, overnight lows will be warming up as well which will limit the amount of recovery. For these reasons a heat advisory has been issued for all non-desert areas south of Pt Conception Sunday through Tuesday morning. At that point models indicate the potential for light to locally moderate offshore flow. There is still quite a bit of uncertainty with this part of the equation which is why the heat hazards turn into Extreme Heat Watches Tuesday through Friday. If gradients end up being more onshore then most areas will likely just remain under heat advisories. Current projections indicate around a 30% chance of 110 or higher in the San Fernando Valley and also a 40% chance of 100 or higher in Downtown LA. Winds in most areas are expected relatively light, under 20mph, however there will be some evening sundowners starting Monday evening. For areas north of Pt Conception, temps will be warming there as well but the hottest temps will hold off until Tue or Wed. .LONG TERM (WED-SAT)...22/219 PM. The extreme heat is expected to continue through the week peaking late in the week. As high pressure continues to build the warm air will start to push north along the Central Coast and will likely need to be issuing additional heat advisories and/or warnings for some or all of the area by Wednesday. Projections show around a 10% chance of 100 degrees in SLO Wed-Fri and a 50-70% chance of highs of 105-110 across interior SLO. In addition, hot Sundowners will be peaking Tuesday and Wednesday evenings across the Santa Ynez Range with strong gusts and temperatures in the 90s and lower 100s likely. Farther south the heat will just get worse later next week with some coastal valleys as high as 113 by Friday and a 20-40% chance of highs 100 or higher in Downtown LA and Camarillo. Some cooling expected to start next Saturday but still at least 6-12 degrees above normal. && .AVIATION...22/1754Z. At 1640Z at KLAX, the marine layer was 600 feet deep. The top of the inversion was at 3100 feet with a temperature of 28 C. High confidence in most of the 18Z TAFs with VFR conds for nearly all airfields. Moderate to high confidence for the TAF at KSBP as there is a 20%-30% chance of IFR cigs/vsbys about 11Z-16Z Sun morning. Otherwise VFR conds are expected. Low to moderate confidence for the TAF at KSMX due to uncertainties with timing of low clouds and IFR/LIFR conds about 06Z-18Z Sun. Timing could be off +/- an hour or two. KLAX...Generally hi confidence in the 18Z TAF with VFR conds expected. However, there is a 20% chance of IFR conds between 13Z-16Z Sun morning. If CIGs occur, the timing could be off by 2 hours. No significant east wind component is expected. KBUR...High confidence in the 18Z TAF with VFR conds expected. && .MARINE...22/103 PM.Moderate to high confidence in Small Craft Advisory (SCA) level winds (20-30 knots) across the Outer Waters at least through Monday night, most prevalent south and west of Point Sal. This may need to be extended through mid week and expanded to all waters again later in the week. SCA winds gusts are also expected across the nearshore waters along the Central Coast this afternoon and evening, then there is a moderate chance for more widespread wind gusts reaching 25 knots during the afternoon and evening hours starting Tuesday and continuing thru Thursday. Gusts of 20-25 knots should reach the western half of the Santa Barbara Channel each afternoon/evening starting Monday and continue thru Thursday. Otherwise widespread SCA conds are not expected for the southern inner waters through the period. && .LOX WATCHES/WARNINGS/ADVISORIES... CA...Extreme Heat Watch in effect from Tuesday morning through Friday evening for zones 38-87-88-349>358-362-366>376-378>383-548. (See LAXNPWLOX). Heat Advisory in effect from 10 AM Sunday to 10 AM PDT Tuesday for zones 87-88-349>358-362-366>376-378>380-548. (See LAXNPWLOX). PZ...Small Craft Advisory in effect until 2 AM PDT Sunday for zone 645. (See LAXMWWLOX). Small Craft Advisory in effect until 11 PM PDT Sunday for zone 670. (See LAXMWWLOX). Small Craft Advisory in effect until 4 AM PDT Tuesday for zones 673-676. (See LAXMWWLOX). && $$ PUBLIC...MW AVIATION...Sirard MARINE...Sirard SYNOPSIS...MW weather.gov/losangeles Experimental Graphical Hazardous Weather Outlook at: https://www.weather.gov/erh/ghwo?wfo=lox  364 FXUS61 KCLE 222133 AFDCLE Area Forecast Discussion National Weather Service Cleveland OH 533 PM EDT Sat Aug 22 2026 .WHAT HAS CHANGED... A Flood Watch has been issued for along and east of I-77 through 10 PM this evening. A Severe Thunderstorm Watch as been issued for most of the forecast area through 9 PM this evening. Main hazards for the severe thunderstorm watch are damaging winds and large hail. && .KEY MESSAGES... 1) Scattered to numerous showers and storms are expected this afternoon and evening. Some storms may turn severe with damaging winds and large hail the main hazards. Flash flooding is possible along and east of I-77. 2) Below average temperatures arrive to end the weekend and start the upcoming week. Periodic lake-enhanced rain showers will primarily impact portions of Northeast OH and Northwest PA late tonight through at least Monday night, with a few showers or storms elsewhere Sunday afternoon/evening. 3) A period of dry and quiet weather is expected the first half of the week. Scattered showers thunderstorms return Wednesday night into Thursday. && .DISCUSSION... KEY MESSAGE 1... The combination of a low-level trough axis and modest warm air/ moisture advection has been fueling some thunderstorms early this morning, primarily over Lake Erie but extending southwest into parts of North Central OH as of 3 AM. While this activity is generally favored to lift east-northeast and diminish this morning, it may still be on the scope as the rest of the world awakens, particularly over and close to Lake Erie. While it may not be an entirely dry morning given this activity, greater shower and storm potential, including a risk for some strong to severe storms, awaits until the afternoon and evening hours. Aloft, a shortwave will dig into the central Great Lakes today into tonight while taking on a neutral to slightly negative tilt. This will encourage a weak surface low to slowly deepen while drifting out of northern Michigan and into southern Ontario late today and tonight. A pre-frontal trough is still expected to cross the area this afternoon and early evening from west to east, with a strong cold front arriving in Northwest OH late this afternoon and surging southeast across the area through this evening. Large scale forcing for ascent will maximize late this afternoon and evening as a vort max rounds the base of the deepening shortwave and rotates into the northern OH/Lake Erie vicinity, though more modest forcing is evident even earlier in the day. Showers/storms are expected to begin developing during the midday or early afternoon timeframe, with activity peaking in coverage, intensity, and organization during the late afternoon and early evening. Showers/storms are expected to exit southeast this evening with the cold front, with activity quickly transitioning to lake-enhanced showers later tonight. Activity will likely blossom along both the pre-frontal trough and a lake breeze near the northeastern shoreline near and east of the I-77 corridor this afternoon, and across Northwest OH along the cold front itself. Given the increasing forcing into the late afternoon/evening and multiple triggers for convection, it's likely that eastern portions of our area see the most widespread convection and greatest overall rain amounts, with some areas likely seeing multiple rounds in quick succession. With that said, nearly all CAMs develop fairly numerous storms along the cold front as it pushes across our western counties, so odds are that a large majority of the area will see a shower or storm this afternoon/evening on the balance. There is some potential for both severe weather and locally heavy rain with storms this afternoon/evening, though the overall setup will not favor higher end convective hazards. Clouds and perhaps some ongoing shower/thunder activity will slow heating today, though weak to moderate, uncapped instability (1000-2000 J/KG of MLCAPE) is expected to develop through the afternoon as low-level lapse rates steepen to around 8C/km. Some pockets of dry air aloft will contribute to modest DCAPE values in the 500-800 J/KG range. These marginal thermodynamics, coupled with increasing forcing and modest deep- layer shear values of 20-30kt, can support loosely organized convection. The primary severe threat today will be locally damaging winds, most likely with any small lines or clusters that evolve but also possible with any more intense cells. Isolated large hail is also possible, mainly with any updrafts that exhibit transient rotation which is most likely within storms along/east of the pre-frontal trough where surface flow will be more backed. While the overall lower-end environment and potential for storms to quickly get "messy" and work over the atmosphere puts a lid on severe potential today, most CAMs have quite a bit of convection across our area with some organization depicted, giving the SPC confidence to introduce a Slight Risk (level 2 of 5) for severe weather for much of the area east of the I-75 corridor (and a Marginal/level 1 of 5 for I-75). In terms of heavy rain potential, storm motions from the west- southwest will be fairly parallel to the incoming cold front, so the potential for multiple rounds and/or transient training does exist. Precipitable water values and warm cloud depths are not especially concerning for efficient rain-rates, though we will need to monitor portions of Northeast OH/Northwest PA for repeated storms or training convection that can still drop localized 2-3" rain amounts. Otherwise, area-average QPF will generally be in the 0.25-1.00" range through this evening, least across Northwest OH and greatest across Northeast OH/Northwest PA. The WPC has introduced a Marginal Risk (level 1 of 4) for excessive rainfall/localized flash flooding across Northeast OH and Northwest PA in their latest excessive rainfall outlook. KEY MESSAGE 2... After pulling a cold front across the area this evening, the surface low and upper trough across the central/eastern Great Lakes will continue to deepen through Sunday while beginning to stack, cut-off, and slow. The system will then start to slowly fill/weaken Sunday night and Monday while drifting to the east- northeast across southeastern Canada and New England. The seasonably chilly airmass pulled in behind the cold front and lingering moist cyclonic flow behind the stacking surface low/ upper trough will give us an early taste of fall to end the weekend and start the week...including some lake-enhanced rain. 850mb temperatures will bottom out at 6-9C Sunday night into early Monday, with 700mb temperatures dipping a bit below 0C as 500mb temperatures fall to around -20C. Most of the area will dry out late this evening into the overnight as the cold front exits, though as cooler west- northwest flow aligns over the ~25C lake waters some lake- enhanced showers will begin developing and moving into Northeast OH/Northwest PA. A vort max and low-level trough axis will cross the region very late tonight into early Sunday, likely causing activity to peak in organization. While some lake effect showers will continue on Sunday across Northeast OH/Northwest PA, the activity will likely lose organization and intensity for several hours after the morning trough passage. Another potent vort max and low-level trough axis will drop in from the northwest late Sunday afternoon and evening, bringing another uptick in lake-enhanced shower activity over and east-southeast of Lake Erie from as far west as the Islands and Sandusky points east. There will also be an uptick in showers across the rest of the area with the trough passage late Sunday afternoon and evening. Chilly, cyclonic west-northwest flow continues through at least Monday night or early Tuesday and some lake effect/ enhanced shower activity remains likely. However, there will likely be a trend for activity to become less intense/organized later Sunday night and beyond as high pressure builds in. A possible exception is Monday night when another vort max and trough passage is hinted at. That could cause one last uptick in the lake-driven showers, especially farther east. In terms of any hazards, instability will be deep enough over the lake for some thunder/lightning potential with the lake- enhanced activity...especially through the first half of Sunday night. The overall set-up with a somewhat shorter west-northwest fetch and some wind shifts through the event isn't overly favorable for intense, banded rainfall with a flash flood risk across the snowbelt. However, rain amounts will gradually add up (especially through Sunday evening) where lake-enhanced showers are most frequent and the potential for localized flooding will need to be kept in mind, especially if parts of Northeast OH or Northwest PA see locally heavy rain today. The heaviest rain amounts will likely occur slightly inland from the lakeshore form the Cleveland area points east-northeast. Otherwise, with cold air aloft and stronger winds towards and above 500mb, any thunderstorms with the trough passage late Sunday afternoon/ evening may produce gusty winds and/or small hail...especially over and downwind of Lake Erie. KEY MESSAGE 3... Locations outside of any lake enhanced rain showers are expected to dry out Sunday night and remain dry into the first half of the week. Lake enhanced rain will gradually dwindle starting late Sunday night and eventually end by Tuesday as discussed above. Overall, this will lend to a tranquil first half of the week across much of the area. Temperatures will slowly rebound towards normal starting on Tuesday. Another trough is expected to dig into the Great Lakes Wednesday night and Thursday. This will likely be accompanied by another surface low and its associated fronts. Chances for showers and some storms may arrive as early as Wednesday afternoon/evening, but are most favored on Thursday with this system. && .AVIATION /18Z Saturday THROUGH Thursday/... Showers and thunderstorms are expected areawide today, especially along and east of I-77 where multiple rounds of storms are likely this afternoon and evening. IFR and lower conditions with reduced visibilities are likely with any thunderstorm today. SPC has a slight risk (level 2 of 5) of severe thunderstorms for this afternoon and evening. Strong to damaging wind gusts up to 50 knots are possible within the strongest storms, along with hail up to 1 inch in diameter. These hazards are likely to be isolated in nature and there is a low probability of impact to any terminal directly. Scattered rain showers and MVFR ceilings may linger across Northeast Ohio and Northwest Pennsylvania tonight, becoming more reserved to Northwest Pennsylvania tomorrow. Outlook...Non-VFR conditions will be likely Sunday through Monday morning with lake enhanced rain showers and isolated thunder possible for areas downwind of Lake Erie in Northeast Ohio and Northwest Pennsylvania. && .MARINE... A cold front will move across the lake through this evening bringing the chance for showers and thunderstorms. Some of these storms could be strong to severe with isolated wind gusts as high as 40-50 knots. Winds will shift around from the west to northwest tonight 15 to 20 knots and continue Sunday through Monday. Waves will increase 3 to 7 feet later tonight and those rough conditions will likely continue Sunday through Monday. Waterspouts will be very possible on Lake Erie starting tonight and lingering through Monday. Small Craft Advisories and Beach Hazard Statements for rip currents have been issued late tonight through Monday afternoon and evening. High pressure will slowly build in Monday into Tuesday with conditions on Lake Erie improving. By Tuesday, winds will be westerly to southwesterly 5 to 15 knots and waves decreasing to 1 to 2 feet. && .CLE WATCHES/WARNINGS/ADVISORIES... OH...Beach Hazards Statement from midnight EDT tonight through Monday afternoon for OHZ009-010. Flood Watch until 10 PM EDT this evening for OHZ011>014- 021>023-032-033-089. Beach Hazards Statement from midnight EDT tonight through Monday evening for OHZ011-012-089. PA...Flood Watch until 10 PM EDT this evening for PAZ001>003. Beach Hazards Statement from midnight EDT tonight through Monday evening for PAZ001. MARINE...Small Craft Advisory from midnight tonight to 5 PM EDT Monday for LEZ144-145. Small Craft Advisory from midnight tonight to midnight EDT Monday night for LEZ146>149. && $$ DISCUSSION...Saunders/Sullivan AVIATION...Kahn/Saunders MARINE...Saunders  652 FXUS66 KMFR 222136 AFDMFR Area Forecast Discussion National Weather Service Medford OR 236 PM PDT Sat Aug 22 2026 .KEY MESSAGES... * Seasonal warmth continues for most areas. * A Red Flag Warning is in place to highlight gusty winds and dry conditions in Klamath, Lake, Modoc, and eastern Siskiyou counties. * Unimpactful weather is expected through the week ahead. Temperatures peak on Monday before returning to seasonal levels near midweek. && .DISCUSSION...An upper trough is passing to the northeast today, which will help to keep temperatures at seasonal levels. Dry air aloft is keeping precipitation chances out of the forecast. Gusty westerly winds east of the Cascades are lining up with ongoing dry conditions to bring critical fire weather concerns this afternoon and evening. A Red Flag Warning is in place for Klamath, Lake, Modoc, and eastern Siskiyou counties to highlight these conditions. With onshore flow along the coast, marine stratus is is expected to rebuild this evening with occasional drizzle possible. With the trough moving away to the northeast through Sunday, temperatures will rise west of the Cascades. A few clouds may pass over Modoc and southern Lake counties, but nothing is expected underneath them. For the week ahead, generally dry southwest flow will bring continuing warm and dry conditions. A weak upper ridge ridge passes over the area on Monday, bringing temperatures 5 to 10 degrees above normal for most areas. The Rogue and Klamath River valleys look to be the warmest areas, with highs approaching or reaching 100 degrees. A passing shortwave may bring very slight thunderstorm chances (5-10%) to southeastern Modoc and Lake counties. Temperatures cool slightly on Tuesday as the weak ridge moves eastward. For midweek, an approaching trough looks to pass to the north, which will help to bring temperatures to seasonal norms by Thursday. Elevated winds are possible in the afternoon and evening of Wednesday and Thursday, but current models have trended down from previous runs which reduces of critical fire weather conditions. These winds will be worth watching as the middle of the week approaches. There's some minor divergence for Friday and beyond, generally limited to whether flow aloft will be zonal or southwesterly. Overall, long-term imagery and ensembles indicate unimpactful weather continues through the end of August. -TAD && .AVIATION...22/18Z TAFs...Marine stratus remains over the Oregon coast and into the Umpqua Valley, but the Umpqua Valley is clearing quickly to start the TAF period. The coast will see stratus last into the afternoon, with a brief period of VFR levels until stratus rebuilds in the evening. MVFR ceilings could return to the Umpqua Valley early Sunday morning. Other inland areas look to stay at VFR levels through the TAF period. Winds become gusty in the afternoon, especially east of the Cascades, then ease into the evening. -TAD && .MARINE...Updated 100 PM PDT Saturday, August 22, 2026...South winds are expected today as a weak front passes through the coastal waters, then winds will shift to the north and increase Sunday morning as a thermal trough develops along the coast. Gusty north winds and steep wind-driven seas will persist through Monday morning. The main belt of stronger winds will push into the offshore waters Monday afternoon and evening, with a southerly surge of winds and fog possible along the inner waters Monday night into Tuesday. Generally light winds and calm seas are then expected through much of next week with low pressure persisting over the northeastern Pacific. && .FIRE WEATHER...Updated 230 PM PDT Saturday, August 22, 2026...An upper level trough and associated dry cold front will pass through the region today, bringinga period of increased winds and critical fire weather conditions. Model guidance shows 700 mb winds, a good proxy for maximum gusts east of the Cascades, will peak at about 40 mph ahead of the front early this afternoon, then diminish through the evening. To the west of the Cascades, particularly in the Rogue and Shasta valleys, gusty northwest winds will peak this afternoon behind the front, gusting to around 20 mph. The deciding factor for potential critical fire weather today will hinge on humidity. Minimum RH west of the Cascades will be too high, so even though winds will be gusty and may approach critical values, conditions should remain below levels of concern. East of the Cascades, however, daytime minimum humidity will trend lower today than yesterday, dropping into the teens or even single digit percentages. Thus, another day of critical fire weather conditions is expected there. A Red Flag Warning is in effect for areas east of the Cascades this afternoon, for FWZs 284/285/624/625. More typical summer conditions return Sunday and persist into early next week. There are some signals for thunderstorm chances across far eastern 285/625, namely the Warner and Hart mountains, 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. && .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 CAZ284-285. PACIFIC COASTAL WATERS...Small Craft Advisory from 9 AM Sunday to 11 AM PDT Monday for PZZ350-356. Small Craft Advisory from 9 AM Sunday to 8 PM PDT Monday for PZZ370-376. && $$  514 FXUS65 KRIW 222150 AFDRIW Area Forecast Discussion National Weather Service Riverton WY 350 PM MDT Sat Aug 22 2026 .KEY MESSAGES... - Continued rain shower activity extending southwest to northeast through the remainder of the afternoon and evening. Storm activity possible across eastern counties late afternoon, and also Yellowstone towards sunset. Severe weather is not likely due to cloud cover at this time. - The chance of showers and storms lingers through much of the week, although today looks the most active. - Temperatures will gradually decrease to near normal levels for much of the week. && .UPDATE... Issued at 1200 PM MDT Sat Aug 22 2026 No real changes to the short term forecast. Rain shower activity been near spot on in relation to HiRes data, especially the trusty NAMNest as per usual. Storm activity has been limited to about nothing due to the continued cloud cover depicted on IR. As a result, severe weather is looking less likely for eastern counties after 4PM. However, storm development looks to still occur through 8PM this evening forming a line that will produce some stronger outflows up to 50 mph (50-60%). Otherwise, instability just won't be there for much, if any, hail. No flooding issues with this progressive pattern. Storms again push out of northeastern Idaho into Yellowstone towards sunset for a couple hours towards midnight before exiting into Montana. Time of day and continued cloud cover limit the instability and any stronger storms. More isolated than scattered for Sunday compared to Saturday. Temperatures for Saturday afternoon will be bumped a bit down not taking into account the cloud cover limiting solar radiation, but a bit more sun for Sunday. Long term forecast is what it is, no changes at this time. && .DISCUSSION... Issued at 141 AM MDT Sat Aug 22 2026 The monsoon has once again arrived across the area, I believe this is the third or fourth appearance so far. So far, it has behaved. We do have some light showers across mainly the western half of the area but nothing heavy so far. The main concern in the forecast will be the potential for heavy rain and possible strong thunderstorms today. Right now, in this meteorologists opinion, potential is mixed for if we will see widespread of either. In regards to heavy rain, the main factor will be the amount of moisture in the atmosphere. Dew points have been slow to rise so far, but they should this afternoon, rising into the 50s in portions of the Big Horn Basin as well as Johnson and Natrona Counties. Precipitable water values should also be rather high. The GFS, for example, has precipitable water values about 175 to 200 percent of normal. This had been overdone by around 15 to 20 percent the past few events though. Even with this, precipitable water values over 150 percent of normal look fairly likely. There will also be some forcing in the form of a shortwave moving in from the west. This should enhance chances for all areas, so everyone will have a chance. The best chance still looks to be in northwestern Wyoming, generally a 1 in 2 chance, and there is decent model agreement in this. As for severe thunderstorms, there looks to be a decent amount of instability. This is especially so in the favored portions of our area, mainly East of the Bighorn Range in Johnson and Natrona Counties. Lifted indices fall as low as minus 4 to minus 5 with close to 1500 J/Kg of surface CAPE here. There is also a decent amount of directional shear in this area. This, plus the ample moisture, may increase the hail threat in this area. We do have a marginal risk of severe weather in portions of Johnson and Natrona Counties, and this could be expanded westward with the 13Z update. All areas could have a thunderstorm but with less instability and shear most storms would be sub severe. However, there are some factors against possible hazards. In regards to flooding and thunderstorms, it is cloud cover. Much of the area, especially western Wyoming, is covered by clouds as I write this around midnight. If it stays mostly cloudy for much of the day, this could limit instability somewhat and decrease the chance of stronger thunderstorms. There will likely be some areas that will be sunnier though, especially further east. And there is one more mitigating factor for heavy rain and possible flooding. With the shortwave moving through, there will be some steering flow today. It won't be strong, but most areas will have 15 to 25 knots at 500 millibars which should keep storms moving somewhat. We continue to have a marginal risk of excessive rainfall, and persistent storms could still cause flooding. But it may decrease the chance somewhat. The shortwave should clear the area by midnight, but some showers will likely linger through the night. As for temperatures, more cloud cover should lower them around 5 to 8 degrees, but it will still be above normal for almost all areas. The forecast from Sunday through much of next week looks fairly similar. We will remain on the edge of the ridge. Some monsoonal moisture will stick around, with precipitable water values remaining above average through much of the period. However, they do look lower than today, so the chance of convection should be somewhat lower. Most guidance favors western Wyoming at this time. However, given the poor performance of the models in regards to timing and placement of the showers and storms, confidence in the details remains low. Temperatures will also cool off somewhat, back down to near to just slightly above normal levels for late August. There continue to be some indications of drier air moving in for the end of next week or next weekend, possibly shutting off the monsoon and bring a period of warm, but not really hot weather for the end of August. && .AVIATION /00Z TAFS THROUGH 00Z MONDAY/... Issued at 350 PM MDT Sat Aug 22 2026 Lingering showers and thunderstorms diminish through about 08z tonight. Gusty outflow winds are the main hazard with this convection. Otherwise, lighter prevailing winds overnight with a partly cloudy sky. Winds increase by late Sunday morning, with isolated showers and thunderstorms possible during the afternoon. Please see the Aviation Weather Center and/or CWSU ZDV and ZLC for the latest information on icing and turbulence forecasts. && .RIW WATCHES/WARNINGS/ADVISORIES... None. && $$ UPDATE...Lowe DISCUSSION...Hattings AVIATION...Wittmann  775 FXUS65 KVEF 222155 AFDVEF Area Forecast Discussion National Weather Service Las Vegas NV 255 PM PDT Sat Aug 22 2026 .KEY MESSAGES... * Above normal temperatures continue through next week. * Isolated storm chances linger into early next week, with best chances in northwestern Arizona and the southern Great Basin. && .DISCUSSION...through Friday. Hotter than normal temperatures will continue through the forecast period as a broad ridge of high pressure remains positioned over the area. High temperatures will top out around 2 to 7 degrees above normal each afternoon, with day to day variations depending on the position of the ridge, cloud cover, moisture, etc. Overnight low temperatures will run around 3 to 8 degrees warmer than normal, providing little-to-no overnight relief in the lower elevations of the Mojave Desert where temperatures will bottom out in the mid-80s to mid-90s. Given the long duration of this anomalous heat, we will see widespread Major-to-Extreme (Levels 3 and 4 of 4, respectively) HeatRisk return during the second half of the week. Southwesterly flow aloft will continue to dry things out, with precipitable water slowly decreasing across the region over the weekend. As a result, storm coverage today and tomorrow will be more isolated in nature, and will be limited to the higher terrain of the Southern Great Basin, Eastern Sierra, and the Arizona Strip where there is a 10 to 30% chance of precipitation this afternoon. Localized moderate-to-heavy rain, lightning, and erratic outflow winds will be the primary threats with any storms that develop. Ensemble guidance continues to show a relative uptick in moisture across northwestern Arizona on Monday. Currently, this slight increase in moisture is reflected in the scattered 15 to 30% rain chances in Mohave County on Monday afternoon. Drying will resume on Tuesday, continuing through the end of the week as we find ourselves under southwesterly flow aloft. && .AVIATION...For Harry Reid...For the 18Z Forecast Package...Southeast winds around 8KT are expected into the early afternoon. Isolated gusts to 15KT are possible with the southeast winds. Around 21Z, winds will become south as gusts over 15KT become more frequent. Winds will diminish this evening around sunset with typical overnight wind patterns through Sunday morning. Similar winds to today are expected Sunday with as southeast winds in the morning become south with gusts to around 20KT in the afternoon. Isolated showers and thunderstorms will develop across the Southern Great Basin this afternoon but are expected to stay far away from the terminals and no local impacts are expected. Temperatures will exceed 100F through 04Z this evening, then again Sunday between 18Z and 04Z. For the rest of southern Nevada, northwest Arizona and southeast California...For the 18Z Forecast Package...Increasing south to southeast winds are expected this afternoon in many locations, gusting 15-20KT at times. West to southwest winds will push into KDAG around 00Z and start gusting over 20KT. Winds will diminish around sunset and follow typical wind patterns overnight. Isolated showers and thunderstorms will develop this afternoon across the Southern Great Basin as well as in the Sierra, will need to watch if anything develops close enough to KBIH that it would impact the airport but currently do not think this will occur. Any precipitation does develop will diminish this evening with a dry night expected. && .SPOTTER INFORMATION STATEMENT...Spotters are encouraged to report any significant weather or impacts according to standard operating procedures. && $$ DISCUSSION...Stessman AVIATION...Nickerson For more forecast information...see us on our webpage: https://weather.gov/lasvegas or follow us on Facebook and Twitter