142 FXUS66 KSEW 240941 AFDSEW Area Forecast Discussion National Weather Service Seattle WA 241 AM PDT Mon Aug 24 2026 .SYNOPSIS... Upper level ridging building over the area today and Tuesday will bring warm and dry conditions to western Washington. An upper level low approaching the region midweek will bring the return on onshore flow, cooler temperatures, and chances of precipitation to the area. Upper level troughing will continue to influence the region heading into the weekend, keeping conditions cooler and cloudier across western Washington. && .SHORT TERM /TODAY THROUGH WEDNESDAY/... Upper level ridging will build over the Pacific Northwest today, while a thermal trough at the surface builds northward along the Washington coast. The ridge axis will shift inland over the Intermountain West by Tuesday, while the thermal trough at the surface also pushes inland. This pattern will bring a warming and drying trend to western Washington for the start of the week. Morning stratus will scatter quicker today and afternoon highs will climb into the mid 70s to mid 80s across the interior lowlands and into the mid 70s along the coast. A combination of northerly and offshore flow will promote continued drying in the low levels and may allow for some smoke from regional wildfires over British Columbia and eastern Washington to make its way back into the area. Tuesday is still on tap to be the warmest day of the week, with afternoon high temperatures expected to climb into the 80s across the majority of the interior and into the low 90s across the Cascade valleys. This will reintroduce Moderate HeatRisk to the valleys as well as the Everett-Seattle- Tacoma metro areas. A pattern change is expected around midweek as an upper level low approaches the Pacific Northwest. This will bring the return of onshore flow and cooler conditions to western Washington, as well as reintroduce a few chances of showers to the area. Overall QPF amounts look to remain light at this time, however cannot rule out a few chances (around 10%) for thunderstorm development along the coast as the low swings northeastward towards Vancouver Island and Haida Gwaii and brings southwesterly flow aloft to western Washington. Afternoon highs will generally be 5 to 10 degrees cooler than Tuesday`s and look to top out in the upper 70s to near 80 across the interior and in the mid 60s along the coast. && .LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/... Ensemble guidance remains in decent agreement with upper level troughing lingering over the region through the second half of the week. This will help maintain onshore flow across western Washington and chances of light showers at times. Thunderstorms will remain possible on Thursday as the aforementioned upper level low swings through the region, but will primarily be confined to the North Cascades. Temperatures will generally trend to near to slightly below normal, with afternoon highs topping out in the low to mid 70s across the interior and in the low to mid 60s along the coast. Morning lows will generally be in the 50s, but may fall into the 40s by later in the weekend. 14 && .AVIATION... An upper level ridge will continue to build into the area through today, with southwest flow aloft across western Washington. Marine stratus along the coast this morning have already brought coastal terminals down to LIFR (KHQM and KCLM). Stratus pushing through the Strait will likely affect interior terminals such KPAE, with IFR/LIFR ceilings this morning. Additionally, we will likely see localized fog at terminals near valleys that could bring deteriorated conditions early this morning. Stratus and fog will burn off later this morning into the afternoon with VFR returning by 18z/20z. Could see some haze at times throughout the afternoon as well. N/NE winds 5 to knots will increase slightly this afternoon, generally around 8 to 12 knots. KSEA...VFR conditions early this morning at the terminal with NE winds 8 to 12 knots. LIFR stratus continues to make its way inland through the Strait - with latest guidance still continuing to suggest a 10% chance of LIFR conditions at the terminal, between 12z-17z. The confidence of stratus reaching the terminal this morning is low, but the 10% probability remains. Otherwise, VFR will continue at the terminal this afternoon. North to northeast winds through the afternoon, generally around 8 to 12 knots. Mazurkiewicz && .MARINE... Surface high pressure remains over the coastal waters today and will continue through Tuesday. Could see patchy fog over the waters this morning as marine stratus continues to push onshore, which may limit visibilities at times. Northerly winds will increase over the coastal waters later this afternoon and evening, with latest probabilities suggesting small craft advisory gusts over the majority of the waters. A Small Craft Advisory has been issued, particularly for gusts up to 25 kts. Onshore flow looks to increase over the area Tuesday into Wednesday, with a westerly push down the Strait of Juan de Fuca that likely will warrant headlines. Coastal seas 4 to 6 feet into Tuesday, with some areas, especially in the outer coastal waters, seeing seas up to 7 feet. Additionally, with period of around 6 seconds, could see choppy seas Monday afternoon and evening. Seas will subside to 3 to 5 feet through much of the week. Mazurkiewicz && .FIRE WEATHER... Warmer and drier conditions are expected across western Washington today and Tuesday as an upper level ridge builds into the region. A thermal trough will also build northward along the coast today, allowing for flow to turn offshore and promoting additional drying in the low levels. Elevated fire weather conditions are likely across the Cascades on Tuesday (the warmest day of the week), with isolated spots expected to approach critical minimum RH thresholds by dipping into the low to mid 20s. A pattern change midweek will bring the return of onshore flow, cooler temperatures, and chances of light precipitation to the area. A 10-20% chance of isolated thunderstorms will be possible, primarily along the coast and North Cascades, Wednesday and Thursday as the upper trough swings northeastward across the region. Upper level troughing then looks to remain over the area into the weekend and should continue to promote onshore flow, excellent overnight humidity recoveries, and cooler temperatures across western Washington, which in turn will help mitigate fire weather conditions through the weekend. 14 && .SEW WATCHES/WARNINGS/ADVISORIES... WA...None. PZ...Small Craft Advisory from 11 AM this morning to midnight PDT tonight for Coastal Waters From Cape Flattery To James Island 10 To 60 Nm-Coastal Waters From Cape Flattery To James Island Out 10 Nm-Coastal Waters From James Island To Point Grenville 10 To 60 Nm-Coastal Waters From James Island To Point Grenville Out 10 Nm-Coastal Waters From Point Grenville To Cape Shoalwater 10 To 60 Nm-Coastal Waters From Point Grenville To Cape Shoalwater Out 10 Nm. && $$

436 FXUS66 KPQR 241125 AFDPQR Area Forecast Discussion National Weather Service Portland OR 425 AM PDT Mon Aug 24 2026 .SYNOPSIS...Upper level ridging and low-level offshore flow develops today, continuing into Tuesday, bringing warmer and sunnier conditions with high temperatures in the lower 90s today and upper 80s Tuesday across the interior lowlands. Wildfire smoke will also begin to increase over the Columbia River Gorge, Upper Hood River Valley, and the greater Portland/Vancouver metro area this morning and then linger through Tuesday; however smoke is not expected to be dense for most locations. Onshore flow arrives by Wednesday and continues thereafter, which will clear any lingering smoke out of the area and bring cooler, more seasonable temperatures through the end of the week and into the weekend. && .SHORT TERM...Now through Tuesday Night...A building upper level ridge will bring a warm start to the work week as a thermal trough develops over the area today. Offshore flow is will develop on the western slopes of the Cascades and Coast range this afternoon, helping support the warmer temperatures. Winds are not expected to be particularly strong but could be gusty in the western Columbia River Gorge with gusts of 25-35 mph possible late this morning through the afternoon. 850 mb temperatures are expected to rise to between 18-22 C supporting a noticeable jump in high temperatures from yesterday. 10th-90th percentiles for highs show a small range in the low to mid 90s for interior lowlands and upper 60s to low 70s along the coast. Offshore winds will also bring some noticeable wildfire smoke to portions of the central and northern Willamette Valley, the Portland metro and the western Columbia River Gorge. Depending on how thick this smoke is, it could impact afternoon highs by knocking them down a degree or two. Afternoon sea breezes return light onshore flow along the coast and western portions of the coast range. A weak passing disturbance may briefly decrease offshore winds along the western slopes of the Cascades during the late afternoon and evening hours but offshore flow returns late in the evening into the overnight hours. Overnight temperatures in the Portland metro and Cascade Valleys and Foothills will be rather mild in the low to mid 60s while temps drop into the mid 50s elsewhere. Troughing over the Gulf of Alaska is expected to slowly drift southeast while a shortwave over the northeast Pacific gets swung toward the PacNW early Tuesday. This will bring slightly lower heights aloft and a decrease in 850 mb temperatures to around 16-18 C but will still support high temperatures in the mid to upper 80s across the interior lowlands and 60s along the coast. Winds will also shift onshore across the entire area. By Tuesday evening, surface high pressure building along the coast will bring a strong marine push of westerly winds. Any lingering wildfire smoke should shift back east of the Cascades by Wednesday. -19 .LONG TERM...Wednesday through Sunday...Confidence remains high heading into the latter half of the week and into the weekend. Cluster analysis is heavily favoring troughing over the PacNW and western Canada with several embedded impulses reinforcing this pattern for several days. This will bring a significant downward trend in temperatures starting Wednesday with highs close to average then gradually dropping into the uppers 70s Thursday and Friday and possibly the mid 70s by Saturday. Precipitation signals remain weak but the best chance for light rain looks to be Saturday, though there is significant model spread this far out. Could see some light drizzle associated with weak frontal passages Thursday morning and a better chance Saturday. -19 && .AVIATION...12Z TAFs...North winds have kept marine stratus just off the coast but have started to see some lower clouds develop right along the strip. This is supporting LIFR conditions at KAST and MVFR conditions at KONP. Guidance is struggling with this set-up with just slight changes in the wind direction likely supporting drastic changes in CIGs and therefore flight level along the coast. Could see intermittent CIG restrictions through 16z along the coast. Inland conditions likely remain VFR though guidance does suggest some stratus developing in the eastern Willamette Valley and Portland metro. Could see some brief CIG impacts at KSLE, KEUG, KTTD and maybe KPDX between through 16-18z. North/northeast winds through the TAF period. Expect breezy winds gusting around of 20 kt at KONP. Around 18-20Z, easterly winds around 8-11 kt are expected to develop at KTTD and KPDX as offshore winds develop through the Columbia River Gorge. The north/northeast winds will also push some wildfire smoke/haze into the Willamette Valley. Smoke/haze will have the potential reduce vertical and slantwise visibilities at times. In addition, temperatures are expected to warm into the lower 90s this afternoon at the inland TAF sites, so be aware of high density altitude which may reduce aircraft performance. KPDX AND APPROACHES...North/northeast winds through the TAF period with more easterly winds developing around 18-20Z. Expect 8-11 kt to develop near and east of the terminal as easterly winds develop through the Columbia River Gorge. Smoke/haze will have the potential reduce vertical and slantwise visibilities at times. In addition, temperatures are expected to warm into the lower 90s this afternoon at the inland TAF sites, so be aware of high density altitude which may reduce aircraft performance. -19/42 && .MARINE...Gusty northerly winds persist through the afternoon across all waters with gusts up to 25 kt expected. Winds decrease from from south to north this evening. The Small Craft Advisory (SCA) from Florence to Cape Falcon will drop off first at 5 PM and the SCA for waters north of Cape Falcon to Cape Shoalwater and the Columbia River Bar are expected to end at 8 PM as winds decrease. A southerly wind reversal arrives early Tuesday morning over the inner waters with gusts up to 15-20 kt expected by Tuesday afternoon over the northern inner waters. This will also bring increasing chances for marine fog beginning early Tuesday morning, especially over the inner waters. Visibilities may fall below 1 SM at times as the southerly winds develop and upwelling occurs. Aside from the increasing winds and potential marine fog, significant wave heights look to remain relatively low at around 3 to 5 ft through Friday. -19/23 && .PQR WATCHES/WARNINGS/ADVISORIES... OR...None. WA...None. PZ...Small Craft Advisory from 8 AM this morning to 8 PM PDT this evening for PZZ210. Small Craft Advisory until 8 PM PDT this evening for PZZ251- 271. Small Craft Advisory until 5 PM PDT this afternoon for PZZ252- 253-272-273. && $$ www.weather.gov/portland Interact with us via social media: www.facebook.com/NWSPortland x.com/NWSPortland

377 FXUS66 KMFR 241044 AFDMFR Area Forecast Discussion National Weather Service Medford OR 344 AM PDT Mon Aug 24 2026 .KEY MESSAGES... * Daytime highs look to be 5 to 10 degrees above normal, especially west of the Cascades. * A 15-20% chance of thunderstorms remains over southeastern Lake and Modoc counties this afternoon and evening. * A passing shortwave will bring critical fire weather conditions (gusty winds and low humidities) to areas west of the Cascades on Monday. A red flag warning is in effect for the southern Oregon Cascades and westward into Jackson County, the Siskiyou Mountains and western/central Siskiyou County. && .DISCUSSION...Today will be the warmest day of the forecast period for most areas. Temperatures west of the Cascades may reach up to 10 degrees above normal, while to the east highs look to be about 5 degrees above normal. A passing shortwave will bring elevated winds into the Shasta Valley, the Klamath Basin, Christmas Valley, and parts of the Rogue Valley. For western Siskiyou County, Jackson County, and western Cascades foothills, these winds align with ongoing dry conditions to possibly reach critical fire weather conditions. A Red Flag Warning has been issued for this afternoon and evening to highlight these concerns. This shortwave is also support slight (15- 20%) thunderstorm chances over eastern Modoc and Lake counties, given its interactions with monsoonal moisture moving over those areas. While the chances for thunderstorms are not high enough to meet Red Flag criteria, any thunderstorms that do develop can still be locally hazardous by bringing lightning strikes or erratic and gusty winds. On Tuesday, an approaching trough around a low pressure system over the Pacific will shift flow to be more southerly. With dry air aloft precipitation is not expected. Temperatures west of the Cascades will drop a bit, but highs across the area look to stay about 5 degrees above normal. A weak front swinging around that trough may bring marine drizzle and some inland cloud cover On Tuesday morning, but significant impacts are not expected. For midweek and into the weekend, the upper trough starts to work against high pressure centered around the Four Corners area. The first low will weaken and move off to the northeast but another low follows to keep the trough in place possibly through Saturday. With this pattern, slow and steady cooling would bring generally seasonable warmth across the area by Friday or Saturday. Upper disturbances may bring elevated breezes on Friday, but details that far out are hard to forecast with high confidence. Overall, the forecast through the rest of August looks to be unimpactful. -TAD && .AVIATION (06Z TAFs)... Marine stratus with IFR/LIFR will redevelop along the coast overnight and persist through late Monday morning. Otherwise, VFR conditions are expected for inland TAF sites. Gusty winds will develop for inland areas late Monday afternoon and evening. Additionally this is a slight chance (20%) for thunderstorms across Modoc and southeastern Lake county Monday afternoon and early Monday evening. Gusty outflow winds may accompany storms on Monday. && .MARINE...Updated 230 AM PDT Monday, August 23, 2026...Gusty north winds and steep seas will persist across the waters through this morning. Winds near shore will ease this afternoon and evening, limiting steep seas to outer waters. A southerly surge of winds and fog along the inner waters is expected tonight into Tuesday. Generally light winds and seas will follow mid-week. && .FIRE WEATHER...Updated 230 AM PDT Monday, August 23, 2026... With ongoing dry conditions, a passing shortwave will bring elevated winds to areas west of the Cascades this afternoon and evening. These winds will be southerly in the Shasta and could approach 30 to 35 mph. The Scott Valley could also see southerly winds approach 20 to 25 mph. In the eastern Rogue Valley, westerly winds could reach 20 to 25 mph. With RHs forecast to be in the 10-15% range, this combination represents critical fire weather conditions as any new fires could quickly spread. A Red Flag Warning for gusty winds and low RHs has been issued for California fire weather ones 280 and 281 as well as Oregon fire weather zones 621, 622, and 623. This Warning will be in place today from 11 AM through 8 PM. Also later today, there are some signals for thunderstorm chances across far eastern 285/625, namely the Warner and Hart mountains. 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 from 11 AM this morning to 8 PM PDT this evening for ORZ621>623. CA...Red Flag Warning from 11 AM this morning to 8 PM PDT this evening for CAZ280-281. PACIFIC COASTAL WATERS...Small Craft Advisory until 11 AM PDT this morning for PZZ350-356. Small Craft Advisory until 8 PM PDT this evening for PZZ370-376. && $$ TAD/TAD/TAD

902 FXUS66 KEKA 240719 AFDEKA AREA FORECAST DISCUSSION National Weather Service Eureka CA 1219 AM PDT Mon Aug 24 2026 .KEY MESSAGES... * Warm interior temperatures are likely again today with a return to seasonable weather for the rest of the week. * Elevated fire weather conditions for the interior this afternoon. && .SYNOPSIS...Dry weather continues for the next week. Warm interior temperatures continue today but return closer to normal for the rest of the week. Coastal stratus will become more persistent this week with only partial clearing likely in the afternoons. && .DISCUSSION...An upper low off approaches the northern California coast today. This troughing pattern has started to funnel moisture into the area off of the coast of Central California Sunday evening. Instability is limited with this moisture surge, but a few high clouds and virga showers are possible for southern Mendocino and southern Lake Counties this morning. Otherwise, dry and warm weather is likely across the area today. Interior temperatures are forecast to be slightly above average with most valleys seeing 90s and the warmest areas nearing 100. Increased vertical mixing from this troughing pattern will support breezier southerly winds of 15 to 20 mph in the interior. This will elevate fire weather concerns this afternoon. See the fire weather section below for more details. The coastal areas are likely to remain in the low to mid 60s. The troughing pattern supports a deep marine layer which, along with light winds near the coast, may keep stratus persistent at the immediate coast through at least Wednesday. The troughing pattern remains in place for the next week. Today will be the last warm day before temperatures return to near normal with high 80s to low 90s for most interior areas. Moisture and instability is limited with this troughing pattern which will limit any thunderstorm potential. Generally mild, seasonable weather is likely for the remainder of the week. /JB && .AVIATION...(6Z TAFs)...Stratus is likely to return early this morning to the coastal terminals. A shallow marine layer is expected to bring LIFR to IFR ceilings with visibility reductions, especially around sunrise. Stratus is likely to lift and scatter by the afternoon, though stratus may only retreat to the immediate coast. Brief IFR to LIFR impacts are possible through the afternoon at both terminals. Interior areas are likely to remain VFR for the next 24 hours. /JB && .MARINE...Northerly winds and steep seas subside today with mild conditions expected by this evening across all waters. Generally mild conditions are expected through Wednesday. Locally breezy southerly winds of up to 20 kts are possible off the Humboldt and Del Norte coasts early this morning. Seas will be dominated by decaying northerly wind waves and a small long period southerly swell. /JB && .FIRE WEATHER...Warm weather today along with a shallow marine layer will combine with breezy southerly winds and low relative humidities in the teens and 20s in this afternoon. Winds will be highest in the Trinity Alps where overnight relative humidity recoveries this morning will be poor. Elevated to locally critical fire weather conditions is expected this afternoon. A deep marine layer returns Tuesday and for much of the week which will raise relative humidity slightly and bring cooler temperatures. Breezy afternoon winds will continue, but the fire weather risk will lower with the higher relative humidity. /JB && .EKA WATCHES/WARNINGS/ADVISORIES... CA... None. NORTHWEST CALIFORNIA COASTAL WATERS... Small Craft Advisory until 9 AM PDT this morning for PZZ450- 455. Small Craft Advisory until 6 PM PDT this evening for PZZ470- 475. && $$ NOTE: The full forecast discussion is now regularly issued between 10 am/pm and 1 pm/am. Additional updates will be issued as needed. Visit us at https://www.weather.gov/eureka Follow us on Facebook and Twitter at: https://www.facebook.com/NWSEureka https://www.twitter.com/NWSEureka For forecast zone information see the forecast zone map online: https://www.weather.gov/images/eka/zonemap.png

922 FXUS66 KMTR 241143 AFDMTR Area Forecast Discussion National Weather Service San Francisco CA 443 AM PDT Mon Aug 24 2026 ...New AVIATION, MARINE... .KEY MESSAGES... Updated at 1200 AM PDT Mon Aug 24 2026 - Temperatures near to slightly below seasonal averages persist within the marine layer through the rest of the week - Warm and dry conditions continue above 1000 feet - Pattern change Friday into the weekend brings cooler temperatures and possible tropical moisture && .SHORT TERM... Issued at 1200 AM PDT Mon Aug 24 2026 (Today and tonight) For the last couple of days we`ve written the tale of a battle between the eastern Pacific trough and the Desert Southwest ridge that has dominated our weather pattern. Today it`s the troughing that will take the upper hand as a cutoff low inches towards the Pacific Northwest, leading to slightly cooler temperatures and cloudier mornings across the region. Another interesting factor today is a weak shortwave trough coming into the region through the morning. The two main global weather models, the European ECMWF and the American GFS, are showing that there could be enough instability, moisture, and lift to maybe, just maybe, support a few high-based thunderstorms developing across the North Bay, particularly over Napa County. This is a very low probability forecast (around 5% chance through around 11 AM), along with a low confidence for storm development. The higher resolution NAM, HRRR, and RRFS models do not show any signs of developing storms, lapse rates aloft are marginal at best, and K-Index values below 20 degrees Celsius suggest no chance for developing thunderstorms. Any precipitation that does develop is also likely to end up as virga, evaporating within the vast dry low layer where relative humidity values as of the 0Z (5 PM PDT) OAK sounding fell into the single digits. Today`s highs range from the 80s into the lower 90s for the inland valleys, the middle 90s to the triple digits across the warmest interior spots, the upper 60s to the upper 70s near the Bays, and the upper 50s to the middle 60s along the Pacific coast. The higher elevations above the marine layer influence will remain rather day, especially during the afternoon and evening hours. Breezy onshore pattern winds will develop this afternoon and evening with wind gusts reaching 20 to 30 mph along coastal jet regions, through favored gaps and passes, and within the northern Salinas Valley. Smoke from the Timber Fire will continue impacting the immediate area around the actively burning fire through the day, with winds aloft lofting the smoke plume over Salinas and Hollister. For air quality information, refer to products issued by the Monterey Bay Air Resources District. && .LONG TERM... Issued at 1200 AM PDT Mon Aug 24 2026 (Tuesday through Sunday) Temperatures rebound Tuesday and Wednesday as the ridge reasserts itself, with the inland valleys reaching highs in the middle 80s to the middle 90s on Wednesday and Thursday while the Bays reach the lower 70s to the lower 80s. A pattern change will begin later on Thursday as a deep trough builds into the West Coast while the ridge begins to inch its way eastwards towards the Southern Plains. It will be interesting to see what the trough will do as the upcoming weekend comes closer and we are better able to refine the forecast. Also worth a mention is the possibility of tropical moisture coming into the region, with our colleagues at the National Hurricane Center tracking Tropical Storm Iselle and three other areas of interest off the coast of Mexico. While the circulations remain far to the south of our waters, the resultant moisture will be captured by the developing trough with a wide variation in just how far north the moisture goes. By way of example, the deterministic European ECMWF model brings a swath of tropical moisture into the San Francisco Bay Area by Friday morning, whereas the deterministic GFS keeps the moisture plume to the south of Monterey County. In addition, wave models are also showing an increase in southerly swells as the tropical eastern Pacific remains active into the early part of next week. && .AVIATION... (12Z TAFS) Issued at 423 AM PDT Mon Aug 24 2026 Mixed bag of VFR/IFR/LIFR early this morning. Status filled north into KSTS and is expected to lift by mid morning with VFR expected to prevail across the Bay Area terminals and inland South Bay airports. IFR/LIFR ceilings over Monterey Bay will give way to VFR late morning, with IFR ceilings returning before sunset. Vicinity of SFO...Low stratus lingers in vicinity of the terminals but not expected to impact ceilings with VFR expected to prevail throughout the day into the evening hours with MVFR/IFR expected to develop around midnight. SFO Bridge Approach...Similar as SFO. Monterey Bay Terminals...A relatively normal diurnal cycle of IFR/LIFR ceilings expected through the forecast period, with current IFR/LIFR ceilings expected to lift by late morning and return in the early evening hours before sunset. Expect periods of breezy onshore flow in the afternoon. && .MARINE... (Today through Saturday) Issued at 423 AM PDT Mon Aug 24 2026 Gentle northwest breezes persist today into Tuesday with slight to moderate wind driven seas. Smoke from the Timber Fire along the Big Sur coast may limit visibility down as low as two miles at times. North-northwest winds begin to increase by the middle of the week, along with an increasing long period southerly swell by the end of the week into next weekend. && .MTR WATCHES/WARNINGS/ADVISORIES... CA...None. PZ...None. && $$ SHORT TERM...DialH LONG TERM....DialH AVIATION...JM MARINE...JM Visit us at www.weather.gov/sanfrancisco Follow us on Facebook, X, and YouTube at: www.facebook.com/nwsbayarea x.com/nwsbayarea www.youtube.com/nwsbayarea

417 FXUS66 KOTX 241117 AFDOTX Area Forecast Discussion National Weather Service Spokane WA 417 AM PDT Mon Aug 24 2026 .KEY MESSAGES... - Warming and drying trend Monday and Tuesday - Minor to moderate heatrisk Tuesday and Wednesday with highs in the 90s. - Breezy winds Wednesday into Thursday with elevated fire weather conditions. && .SYNOPSIS... Temperatures warm Monday into Tuesday with afternoon highs in the 90s by Tuesday. The heat begins to break down Wednesday into Thursday with an increasing risk for breezy winds and mountain thunderstorms. && .DISCUSSION... Today through Wednesday: A ridge will build into the region along the Continental Divide while a trough digs in off the coast. A similar pattern will be setting up from this past weekend. The ridge will be in place for a couple of days leading to dry, warm pattern. Highs will climb back into the 90s. Moderate HeatRisk will return for most lowland locations on Tuesday and Wednesday. As the trough begins to press into the region, a weak band of instability will slide through the Lower Idaho Panhandle and bring a less than 10% chance for showers and isolated thunderstorm on Tuesday night. Late Wednesday and Thursday: The trough begin to push into the region on Wednesday and slowly track east. Ensembles have weak instability over the Cascades, northern mountains, and the Idaho Panhandle. Precipitable water amounts are 0.75-0.9 of an inch. Winds will increase through the Okanogan Valley and Waterville Plateau with gusts in the 20-30 mph range. Wednesday highs will be in the 90s before dropping into the 80s on Thursday. Friday through Sunday: The trough will struggle to displace the ridge over Central US. Ensembles have the trough pattern stalled over the region through the weekend. Drier air will push into the region as precipitable water values drop to around half an inch. While meaningful amount of rain is not expected, the trough will drop highs back into the upper 70s and 80s through the end of the week. /JDC && .AVIATION... 12Z TAFs: High pressure will deliver light winds, and mostly clear skies through 12z Tuesday. Smoke production from Little Giant and Sisi Fires in Chelan county will continue which may result in some restrictions to visibility at times for KEAT/KMWH. However latest HRRR smoke model keep levels on the lighter side for these two sites with VFR conditions favored. FORECAST CONFIDENCE AND/OR ALTERNATE SCENARIOS: High confidence in VFR conditions outside of visibility restrictions near wildfire sources in Chelan county. High confidence in VFR conditions through 12z Tue for KGEG/KSFF/KCOE/KPUW/KLWS and moderate confidence in VFR conditions for KEAT/KMWH. JW ----------------------- 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 53 86 55 95 59 92 / 0 0 0 0 0 10 Coeur d`Alene 53 86 55 95 60 93 / 0 0 0 0 10 10 Pullman 46 86 49 94 53 90 / 0 0 0 0 0 10 Lewiston 56 91 60 99 65 96 / 0 0 0 0 10 10 Colville 43 85 45 92 49 93 / 0 0 0 0 10 10 Sandpoint 46 82 50 91 55 92 / 0 0 0 0 10 20 Kellogg 51 84 53 92 57 92 / 0 0 0 0 10 20 Moses Lake 54 89 56 95 57 93 / 0 0 0 0 0 0 Wenatchee 61 88 64 94 67 93 / 0 0 0 0 0 0 Omak 53 87 58 94 61 94 / 0 0 0 0 0 0 && .OTX WATCHES/WARNINGS/ADVISORIES... WA...Air Quality Alert until further notice for Central Chelan County- Okanogan Highlands-Okanogan Valley-Upper Columbia Basin- Waterville Plateau-Wenatchee Area-Western Chelan County-Western Okanogan County. ID...None. && $$

922 FXUS66 KPDT 241015 AFDPDT Area Forecast Discussion National Weather Service Pendleton OR 315 AM PDT Mon Aug 24 2026 .KEY MESSAGES... 1. Ridge of high pressure overhead will keep temperatures above seasonal normal through Wednesday 2. An upper level low approaching the region will bring increased winds Wednesday increasing fire weather concerns. && .DISCUSSION... Current night time satellite shows little to no cloud cover over the region. Looking at overnight temperatures to be inn the upper 50s to low 60s through the Basin, Gorge and along the foothills of the Blues. Elsewhere will see low 50s. Models show a ridge of high pressure building over the region today and persisting through early Wednesday bringing with it dry and above seasonal average temperatures. Looking at in house calculations, temperatures are expected to be anywhere from 5 to 10 degrees above seasonal average today, increasing to near 15 degrees tomorrow and Wednesday. Looking at HeatRisk probabilities, Tuesday?wednesday will be the peak with 70-80% probabilities of areas reaching Moderate HeatRisk (level 2 of 4) across the Columbia Basin and Central OR. There is also a low to medium risk of areas in the Columbia Basin seeing Major HeatRisk (3 of 4) with 20-40% probabilities. Moderate HeatRisk affects those who are sensitive to heat, especially those without cooling/hydration, while Major HeatRisk affects anyone without cooling/hydration. Wednesday models show the upper level low off the coast of the PacNW begin to push its way onshore. By Wednesday afternoon, models show the leading edge of the low beginning to move towards the Cascades. As the leading edge of the low approaches the Cascades, short term deterministic models show a tightening of the pressure gradients along the crests. Looking at raw ensembles, there is 60-80% confidence for winds of 15-25 mph with gusts to 35 mph possible through the Columbia River Gorge, Kittitas Valley and along the foothills of the Blue Mountains. With the increased winds and NBM showing relative humidities being in the teens to low 20% across the region, there is elevated to locally critical fire weather concerns that could develop across the lower elevations zones (65-75%). Thursday onwards, models show the upper level low to continue to persist just to the west of the Cascades bringing persistent southwesterly flow to the region. This will keep the region under dry and breezy conditions. && .AVIATION /12Z TAFS THROUGH 12Z TUESDAY/... VFR conditions will persist through the forecast period. Winds will remain below 12 knots through the period. Confidence in low level smoke causing MVFR VIS concerns is low, however PSC/PDT/DLS/ALW will see a slight decrease to 6SM as the smoke settles in the morning. This will persist through 18-20Z. && .FIRE WEATHER... Fire weather concerns are moderate through the forecast period as only relative humidity is low with no winds. The next day of concern for elevated to locally critical fire weather concerns will be Wednesday as an upper level low brings increased winds of 15-25 mph winds and gusts to 35 mph with relative humidities in the teens to low 20s. && .Preliminary Point Temps/PoPs... PDT 91 54 93 59 / 0 0 0 0 ALW 93 61 95 66 / 0 0 0 0 PSC 93 56 95 59 / 0 0 0 0 YKM 90 61 95 61 / 0 0 0 0 HRI 92 57 95 61 / 0 0 0 0 ELN 86 57 92 60 / 0 0 0 0 RDM 91 50 94 49 / 0 0 0 0 LGD 93 55 97 57 / 0 0 10 10 GCD 95 56 95 57 / 0 0 0 0 DLS 93 64 96 63 / 0 0 0 0 && .PDT WATCHES/WARNINGS/ADVISORIES... WA...Air Quality Alert until noon PDT today for WAZ026-522-523. OR...Air Quality Alert until noon PDT today for ORZ041-044-049-050- 502-503-505>507-509>511. && $$ DISCUSSION...90 AVIATION...90 FIRE WEATHER...90

711 FXUS65 KREV 240941 AFDREV Area Forecast Discussion National Weather Service Reno NV 241 AM PDT Mon Aug 24 2026 .KEY MESSAGES... * Isolated showers and thunderstorms are possible this afternoon and evening in Northeastern California and Western Nevada. * Smoke from the Hawk Fire will continue to impact air quality and visibility, especially near the Reno/Sparks metro area today. * Increased winds will bring elevated to critical fire weather to the region along with potential recreational impacts by midweek. && .DISCUSSION... For today, forecast guidance shows the CWA with a generally southwesterly flow aloft being underneath the western portion of an upper air ridge residing over the southwestern CONUS. Models also show a shortwave disturbance traveling through the flow over N CA and then into OR during the afternoon and evening hours. This feature looks to be the driver for precipitation chances today as there is a 15-25% chance for isolated showers and thunderstorms for NE CA and W NV today with the higher end chances expected in areas closer to the OR border. The window for precipitation looks to be between 1-8 PM today according to the latest hi-res guidance though some lingering showers may be possible in eastern portions of Pershing and Churchill Counties before midnight. When looking at the latest convective parameters from CAMs, MUCAPE values appear to go up to around 500 J/kg with DCAPE values exceeding 1000 J/kg. This will allow storms today to be capable of producing wind gusts up to around 45-55 mph once again. Storms also look to have quicker storm motions today, so dry lightning could be possible especially in areas closer to the OR border. Not anticipating a flooding threat with storms today as there is a dry surface layer seen in the model soundings, but brief bouts of heavier rainfall can be possible with PW values up to around 0.7 inches. As for the Tahoe region and the Sierra, dry conditions are to be expected today. The latest run of the HRRR near-surface smoke product shows that smoke from the Hawk Fire will continue to cause impacts today in W NV particularly within the Reno-Sparks metro area. Lighter winds this morning will allow smoke to settle which can reduce visibility and degrade air quality. Area winds expect pick up in the afternoon with gusts up to around 25-30 mph when smoke concentration increases allowing smoke to have better dispersion. But when winds decrease overnight, smoke will settle again. Those sensitive to poor air quality will want to continue to monitor airnow.gov today for the latest air quality information. Daytime high temperatures through Thursday are forecast to be in the lower to middle 90s for NE CA and W NV valleys with Sierra communities in the middle 70s to lower 80s range. By Friday and going into the weekend, the forecast shows slightly milder temperatures with the valleys in the upper 80s to lower 90s and the higher Sierra elevations in the 70s. The main concern going through the rest of the week is increased winds Tuesday through possibly Saturday as a PacNW upper low moves into SW Canada. The latest NBM run continues to show around a 50-80% probability for maximum wind gusts over 30 mph on these days within the region. These winds will cause elevated to critical fire weather (see Fire Weather Section for more information) and recreational concerns on area lakes within the region, especially for the second half of the week. Please continue to watch for forecast updates especially if fire or wind products need to be issued. While the remainder of the week looks to be mostly dry, some models are hinting at around 10-20% chances for precipitation in the Sierra and W NV on Friday. -078 && .AVIATION... VFR conditions will prevail for the area TAF sites today and tonight with winds gusting up to 20-25 kts between 24/19Z-25/03Z. Smoke from the Hawk Fire may continue to reduce visibilities at KRTS and in the vicinity of KRNO through the day, but the latest forecast is not calling for sub-VFR conditions at area terminals. Will continue to monitor this situation and amend TAFs if needed. The increased winds will aid in smoke dispersion this afternoon, but smoke expects to settle in portions of W NV going through the night when winds decrease. As for precipitation chances today, there looks to be around a 15- 25% chance for isolated showers and thunderstorms in NE CA and W NV beginning around 24/21Z with portions closer to the the OR border seeing the higher end chances. By 25/03-04Z, precipitation chances look to exit out of the region to the east. Otherwise, conditions look to be mostly dry through the middle of the week with afternoon wind gusts increasing to around 30 kts. -078 && .FIRE WEATHER... Breezy W/SW winds with gusts up to around 25 mph and RH reductions of 20-25% will support elevated fire weather conditions again this afternoon across the Sierra Front and NE CA, including the Hawk Fire. Slightly better overnight RH recoveries are forecast around the 40-50% range near the Hawk Fire. Another concern today is that there is potential for dry thunderstorms this afternoon with the latest SPC fire weather outlook highlighting areas along the OR border where there is a 15- 25% for showers and thunderstorms generally between 1-8 PM today. The latest HRRR shows CAPE values up to 500 J/kg signaling an unstable environment that can support vertical plume growth with the moist mid-level seen in forecast soundings. Going through the rest of the week, increased winds with gusts upwards of 35 mph (40 mph in wind prone areas) are expected Tuesday through possibly Saturday, mainly for the Sierra Front and NE CA. The SPC`s Fire Weather Outlook for these days also highlights these areas with 40% chance of critical fire weather conditions due to increased winds and low RH. Currently, days with the most widespread critical fire weather conditions in these areas looks to be Wednesday through Friday. Please continue to watch for further updates in case fire products need to be issued. -078/Justin && .REV Watches/Warnings/Advisories... NV...None. CA...None. && $$

913 FXUS66 KSTO 231833 AFDSTO Area Forecast Discussion National Weather Service Sacramento CA 1133 AM PDT Sun Aug 23 2026 .KEY MESSAGES... - Dry with seasonable high temperatures through the next week. - Slight but uncertain chance for isolated thunderstorms on Monday. && .DISCUSSION... Some high clouds visible moving across interior NorCal today on GOES West Satellite imagery. Still, conditions remain dry with seasonable temperatures. Valley highs primarily in the 90s today, with 80s to 90s at higher elevations. Breezy onshore conditions, though less windy today than the last few days. The remainder of the week, upper level low pressure to the northwest and high pressure to the east will continue the pattern of periodically breezy onshore winds, with seasonable high temperatures and cooler overnight lows. Early Monday morning there is a less than 5% chance for an isolated thunderstorm to develop over the western portion of the southern Sacramento Valley, though there is very little confidence in this occuring. Monday afternoon and evening, there is up to a 10% chance for isolated thunderstorms along and east of the Sierra crest, including near the Burney Basin. && .AVIATION... VFR conditions continue through the TAF period, with FEW to SCT clouds moving through the Sacramento sites this afternoon/evening. Overnight another cloud deck shifts through Interior Northern California bringing SCT clouds, with VFR ceilings. Winds during the TAF period will be breezy at times near the Delta, but overall around 5-10kts elsewhere. && .STO WATCHES/WARNINGS/ADVISORIES... None. && $$

461 FXUS65 KMSO 240938 AFDMSO Area Forecast Discussion National Weather Service Missoula MT 338 AM MDT Mon Aug 24 2026 .DISCUSSION... KEY MESSAGES: - High pressure rebuilding today with warming temperatures and light diurnal winds. - Thunderstorm chances expand northward Tuesday and Wednesday. High pressure will rebuild across the Northern Rockies today bringing stable conditions and generally light winds. High temperatures will be on the uptrend, topping out about 10 degrees above seasonal norms by Tuesday and Wednesday. Monsoonal moisture will begin spreading northward for Tuesday, introducing shower and thunderstorm chances primarily up toward the I-90 corridor. By Wednesday, deeper monsoonal moisture will begin to encompass most of the region increasing the chances and coverage of showers and thunderstorms. A mix of rain-producing storms will intermingle with mostly dry thunderstorms elevating the risk for more lightning-caused fire starts. Ensemble guidance continues to show agreement on a Pacific Northwest trough returning into the forecast by the end of this coming week into next weekend. At this time, there aren`t many details on exact impacts or timing, but we can expect moderating temperatures, and an increase in winds over a couple days which may lead to another window of elevated fire weather conditions later this week. && .AVIATION...High pressure is rebuilding over the region bringing widespread VFR weather conditions. Generally, light and diurnal/terrain driven winds can be expected at all terminals. Warming daytime temperatures over the next couple days will noticeably increase density altitudes once again. Regional and local wildfire smoke may cause localized areas of degraded slant -range visibility at times. Shower and thunderstorm chances begin to increase northward by Tuesday and Wednesday. && .MSO WATCHES/WARNINGS/ADVISORIES... MT...None. ID...None. && $$

666 FXUS65 KBOI 241230 AFDBOI Area Forecast Discussion National Weather Service Boise ID 630 AM MDT Mon Aug 24 2026 .UPDATE...Updated aviation discussion. && .KEY MESSAGES... - Scattered thunderstorms south of a line from Burns OR to Jordan Valley OR to Twin Falls ID, this afternoon and evening. - Thunderstorms capable of producing outflow winds up to 55 mph this afternoon and evening. - Little chance of thunderstorms the rest of the week, except a slight chance in the central ID mountains Wednesday afternoon, and near the NV/ID border Friday-Sunday afternoons. - Warming Monday and Tuesday, holding level Wednesday, then gradually cooling the rest of the week. && .SHORT TERM /Through Wednesday Night/... Issued 430 AM MDT MON AUG 24 2026 Upper level ridge will rebound over the area and bring warmer temperatures today and monsoonal moisture from the south. Moisture values in the atmosphere increase from the 20th percentile to the 85th percentile by this evening. A shortwave moving in the southwest flow aloft will trigger scattered showers and thunderstorms over far SE Oregon and southern ID south of the Snake Basin, generally from Burns OR, to the Owyhee Mountains to Twin Falls ID and areas south. Storms will generally weaken into showers as they move northeast into the Snake Basin, but outflows up to 55 mph and blowing dust will still be a threat. Showers taper off overnight into Tuesday. Lingering moisture will remain over the area for isolated thunderstorms on Tuesday afternoon over southwest Idaho. A weak wave will move over the region on Wednesday with mostly cloudy skies. Thunderstorm development will be limited on Wednesday due to cloud cover, but isolated thunderstorms over southwest Idaho possible. && .LONG TERM /Thursday through Monday/... Issued 430 AM MDT MON AUG 24 2026 An upper level trough off the West Coast will push the monsoon moisture south and east of our area. Height falls throughout the period will allow for a slight cooling trend. Temperatures will be around 5 degrees above normal Thursday, before cooling to near normal Friday and Saturday, and slightly below normal on Sunday. Uncertainty begins to increase late this week, following the lifting of the initial trough and associated frontal passage as tropical activity in the Pacific enhances the jet stream. Models do not handle the energy transfer well in these situations so expect lots of changes in the far extended period. && .AVIATION /12Z Monday through Tuesday/... Issued 623 AM MDT MON AUG 24 2026 VFR. Areas of wildfire smoke. Scattered thunderstorms this afternoon south of a line from KBNO-KMAN-KTWF. Surface winds: variable 5-10kt, except gusty erratic outflow winds up to 45kt possible this evening causing BLDU. Winds aloft at 10kft MSL: SW 10-20 kt. KBOI...VFR. Isolated showers this evening. Surface winds: variable 5-10kt. Gusty outflow winds up to 35kt possible this evening. && .BOI WATCHES/WARNINGS/ADVISORIES... ID...Red Flag Warning from noon today to 8 PM MDT this evening for IDZ423-426. OR...Red Flag Warning from 3 PM this afternoon to 8 PM PDT this evening for ORZ670>672. && $$ www.weather.gov/Boise Interact with us via social media: www.facebook.com/NWSBoise www.x.com/NWSBoise AVIATION.....KA SHORT TERM...KA LONG TERM....KA

699 FXUS65 KLKN 240923 AFDLKN Area Forecast Discussion National Weather Service Elko NV 223 AM PDT Mon Aug 24 2026 .KEY MESSAGES... * Subtropical moisture will help to fuel afternoon and evening thunderstorms through the middle of next week * Some showers and thunderstorms could produce brief moderate to heavy rain with the main threat of debris flows on recently burned areas * Cooling trend continues today as mid-level moisture and increasing cloud cover continues its northward trajectory && .DISCUSSION... (Today through next Monday) WEATHER PATTERN OVERVIEW: One more afternoon and evening of unrestricted monsoonal flow will continue to bring shower and thunderstorm chances for the Silver State, but High pressure shifting west from the plains looks to first limit, then cutoff moisture flow. Monday afternoon and evening there will again be a 20% to 50% chance of isolated to scattered showers and thunderstorms, but these chances drop to 10% to 20% Tuesday, then rise a bit to 10% to 30% Wednesday afternoon and evening. Storm chances look to drop below 10% Thursday into the weekend, the main reason will be the subtropical high pressure ridge now over the southern plains builds west into Arizona. Storm modes through Monday still favor more wet storm modes, but there will still be a chance for a few dry thunderstorms, both as storm motion increases due to increasing southwesterly flow and from mid level moisture decreasing. Tuesday and Wednesday chances for dry thunder will increase, but storm coverage will shift east as drier air returns from the west. Common hazards for storms will include gusty outflow winds up to 50 MPH, ground lightning strikes, and brief heavy rainfall. Thursday through Monday, models may have finally settled on a pattern change. Both the GFS and ECMWF still show that the upper ridge will try and work its way back west, shifting the upper flow back to a WSW direction as it does so. What is interesting is models are now showing that the ridge will stay farther south over the US/Mex border allowing for a longwave trough to set up offshore of the Pacific northwest. This will bring a more westerly mid and upper level flow, which would be dry, but it would also be cooler given the lower forecast heights. Still this is a just a recent agreement from the models, so overall confidence remains mixed for the extended until this consensus holds firm. Temperatures even with the pattern change look to hold in the low 80s to low 90s, with overnight lows ranging into the mid 50s to mid 60s. Winds will be breezy through the weekend and into the new week as winds shift more south to southwest in line with the upper level flow pattern at speeds of 10 to 20 MPH with gusts up to 30 MPH possible. Winds look to shift back to the west to SW Thursday through the weekend. FORECAST CONFIDENCE & DEVIATIONS: There is high confidence a daily 20% to 50% chance for isolated to scattered showers and thunderstorms for Nevada through Monday. There is moderate confidence in a 10% to 30 % chance for a mix of isolated dry and wet thunderstorms Tuesday and Wednesday. There is high confidence in dry conditions returning to the Great Basin Thursday trough Sunday of next week. There is low-moderate confidence in the upper pattern Thursday through Monday as models now seem to agree on keeping NV under WSW flow between as upper level ridge over Arizona, and a trough off the Pacific NW. && .AVIATION... VFR conditions look to be the primary flight conditions through Monday evening. Winds will be out of the south to southwest at 5KT to 15KT with gusts to 25KT possible for all terminals. VCTS will be possible during afternoon and evening hours for KBAM, KEKO, KELY, and KENV as monsoonal flow keeps a 20% to 50% chance for isolated to scattered showers and thunderstorms. Although not likely, a stray VCTS will be possible for KTPH, and KWMC, chances will be near 10% Monday afternoon. && .FIRE WEATHER... One last day of unrestricted monsoonal moisture will keep a 20% to 50% chance for isolated to scattered showers and thunderstorms for central and northern Nevada Monday afternoon and evening. Hazards from storms will include gusty outflow winds up to 50 MPH, Ground lightning strikes, and brief heavy rainfall. High Pressure ridge to the east will begin to impinge on moisture flow by Tuesday and Wednesday dropping storm coverage to isolated and storm chances to 10% to 30% for a mix of wet or dry thunderstorms. High Pressure looks to cut off monsoon flow fully by Thursday bringing drier conditions that will last through Monday of next week. Winds will be out of the south to southwest at 10 to 20 mph with gusts up to 30 MPH possible, after Thursday winds shift to west to southwest with similar speeds through the weekend. && .LKN Watches/Warnings/Advisories... None. && $$ DISCUSSION...98 AVIATION...98 FIRE WEATHER...98