724 FXUS66 KSEW 281613 AFDSEW Area Forecast Discussion National Weather Service Seattle WA 913 AM PDT Mon Sep 28 2026 .SYNOPSIS...Surface high pressure weakening today. Zonal flow aloft. Next system moving down British Columbia coast moving through the area Tuesday. Post frontal convergence zone Tuesday evening. High pressure, both surface and aloft, rebuilding Wednesday. Upper level ridge remaining over the area through the weekend. Thermally induced surface trough moving up the Oregon coast reaching the Washington coast Saturday turning the low level flow offshore. Surface trough moving inland Sunday. && .SHORT TERM /TODAY THROUGH WEDNESDAY/...Dry conditions continue into the afternoon. Next system to move into Western Washington currently near Haida Gwaii and slowly moving southeast. High clouds out ahead of the system will spread over the area this morning into the afternoon hours. Chance of rain by the evening along the north coast. Highs in the 60s. Front continuing to slowly move southeast tonight. By 12z Tuesday front still north of the area. Surface pressure gradients tightening up over the Northwest Interior as the front approaches. Have issued a wind advisory for the Northwest Interior and the San Juans beginning at 2 am Tuesday morning for southeast winds increasing to 20 to 30 mph with gusts 40 to 45 mph. Rain out ahead of the front reaching the north coast and Northwest Interior by midnight. Chance of rain as far south as Olympia by early Tuesday morning. With the cloud cover lows will be much warmer than the previous mornings, in the lower to mid 50s. Front slowly moving through Western Washington Tuesday. Rain over most of the area by mid morning. Front moving through the Northwest Interior and north coast early afternoon. Winds easing behind the front. Highs in the lower to mid 60s. Front moving through the remainder of the area by early in the evening with rain coming to an end. Post frontal convergence zone over Snohomish county will dissipate after midnight. Not much in the way of cool air behind the front with just limited shower activity outside the convergence zone. Lows in the mid 40s to lower 50s. High pressure, both surface and aloft, building over Western Washington Wednesday. Winds easing overnight. Patchy fog developing early in the morning. What little fog that does form will be gone by mid morning. Skies clearing with plenty of sunshine especially in the afternoon. Highs in the lower to mid 60s. JD/Felton && .LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/...Extended models have finally gotten rid of the slight chance pops for Thursday and Friday. Upper level ridge over the area with high pressure at the surface. Thermally induced surface trough moving up the Oregon coast Friday extending north to the Washington coast Saturday. Low level flow turning offshore. In this scenario this time of year it is not uncommon for the coast to be the warmest location in Western Washington. Thermally induced surface trough moving inland Sunday making it the warmest day for the interior. Lows in the 40s Thursday morning, mid 40s to lower 50s Friday through Sunday morning. Highs in the mid to upper 60s Thursday and Friday, 60s and lower 70s Saturday and Sunday. Even with the normal high in Seattle starting October at 66 degrees, the normal number of 70 degree plus in Seattle in October is only 2. Out of the 170 days total ( in 81 years of records ), 51 ( 30 percent ) are 75 degrees or warmer. 75 percent of the 70 degree plus days in October have occurred in the first 10 days of the month and all of the 75 degree plus days have occurred in the first 16 days of the month. Felton && .AVIATION...Zonal flow aloft with occasional shifts to the NW at times today, strengthening tonight as gradients tighten. Light and variable surface winds this morning becoming southerly 5-10 kt this afternoon in advance of approaching front. Speeds increase further this evening and overnight generally ranging 10-15 kt with gusts up to 20 kt possible. Widespread VFR conditions in place this morning. Cigs expected to lower throughout the day as incoming front approaches, however VFR expected to persist for the majority of the TAF period for most terminals. Western-most terminals will begin to encroach on MVFR conditions this evening between 03-06Z while remaining terminals likely will not see these conditions emerge until around 12Z Tuesday as rainfall spreads across the area. KSEA...VFR conditions through today and tonight even though cigs will gradually fall throughout the day. MVFR conditions expected to develop near the end of the TAF period, around 10-12Z, as front draws nearer. Start of precip also expected during this time frame. Light and variable winds this morning before turning more southerly at 5-10 kt this afternoon. SW winds 10-15 kt with gusts up to 20 kt after 03Z tonight with best chances for gusts holding off until closer to FROPA starting in the aforementioned 10-12Z time frame. 18/41 && .MARINE...The next frontal system arrives later today into Tuesday with increasing southerly winds over all waters - Small Craft Advisories are in effect for most waters, although it appears the Northern Inland Waters run a good chance for consistent gusts exceeding Gale criteria. As such, have upgraded the SCA there to a Gale Warning. Winds will turn more westerly through the strait Tuesday afternoon. Meanwhile, expect elevated seas with swells reaching 10-11 ft. Onshore flow will ease late Tuesday night. The flow will then turn offshore on Wednesday with a thermal trough along the coast. Light offshore flow continues through the end of the week. 18/33 && .SEW WATCHES/WARNINGS/ADVISORIES... WA...Wind Advisory from 2 AM to 2 PM PDT Tuesday for Lowlands of Western Whatcom County-San Juan County. PZ...Small Craft Advisory from 5 PM this afternoon to 5 PM PDT Tuesday for Admiralty Inlet-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-Puget Sound and Hood Canal-West Entrance U.S. Waters Strait Of Juan De Fuca. Small Craft Advisory from 5 PM this afternoon to 5 AM PDT Wednesday for Central U.S. Waters Strait Of Juan De Fuca- East Entrance U.S. Waters Strait Of Juan De Fuca. Gale Warning from 11 PM this evening to 5 PM PDT Tuesday for Northern Inland Waters Including The San Juan Islands. && $$

932 FXUS66 KPQR 282100 AFDPQR Area Forecast Discussion National Weather Service Portland OR 200 PM PDT Mon Sep 28 2026 .SYNOPSIS...Dry weather continues through this evening, but expect sunny skies to give way to increasing clouds as a frontal system approaches from the north. On Tuesday, this decaying frontal system drops south across northern portions of the area bringing chances for rain through late Tue night, with the highest probabilities along the Washington and north Oregon coast and Coast Range. Dry weather is favored again by Wednesday with temperatures trending warmer this weekend. && .DISCUSSION...Now through Monday...Satellite imagery shows mostly clear skies over the forecast area early this afternoon. But, mid to high level clouds are expected to increase through tonight as a weather system to the north gradually shifts southward. The weak ridge of high pressure over the area will be replaced by zonal flow over the region. With increasing cloud cover, do not expect overnight temperatures to cool as much as this morning`s lows. A decent plume of moisture associated with the frontal system is currently impacting Vancouver Island, but is expected to weaken as it drops south into western Washington as upper level support quickly moves eastward across Canada. But, there appears to be enough lingering moisture to bring some rain to the north Oregon coast and possibly into the Portland Metro area and locations northward. Latest guidance suggests there is around a 40-60% chance for 0.25 inch of rainfall from Tillamook northward, with about a 50% chance for a half inch of rain in the Willapa Hills. Rain will likely be more spotty with light amounts expected across portions of southwest WA and the Portland metro, generally less than 25% chance for exceeding 0.10 inch, while conditions Salem southward remaining dry. Widespread dry conditions return by Wednesday morning, and likely continuing through the remainder of the week into the weekend. The one caveat includes a weak weather system potentially clipping northern portions of our forecast area again Thursday into Friday. But, most ensemble members are pushing the system farther north, with only 10% or less showing rain. Temperatures remain fairly seasonable through the end of September. By the weekend, models and their ensembles are in fairly good agreement of a more pronounced ridge of high pressure building over the region. This would maintain dry weather and potentially trend afternoon temperatures around 5-10 degrees above normal for early October. Clusters hint at more uncertainty though heading into early next week. /DH && .AVIATION...Through 18Z Tuesday...Northwest flow aloft becomes westerly on Tuesday as high pressure gradually weakens over the area. Predominately VFR conditions expected today with increasing high level clouds. Stratus is likely to return to the coast by 00-03z Tuesday as a weak front begins pushing into southwest WA. Chances for light rain increase after 09-12z near KAST as conditions likely to deteriorate to lower MVFR along with a 40-50% chance of IFR conditions after 15z Tuesday. Chances for IFR near KONP also increase to around 40-50% by 10-12z Tue. CIGs are also expected to lower inland Tuesday morning, with around a 30-50% chance of MVFR after 16z Tue, mainly north of KSLE. Winds increase slightly along the coast to around 6-10 kt from the west, turning southerly by this evening and overnight. KPDX AND APPROACHES...VFR conditions are expected through at least 15z Tuesday. Stratus likely increases Tue morning with lowering CIGs, and around a 30-50% chance of MVFR after 16z Tue. Light winds become southerly 4-6 kt Tue morning. /DH && .MARINE...High pressure will continue to weaken as a frontal boundary approaches the coastal waters tonight. Southerly winds are expected to increase overnight into Tuesday morning with gusts most likely peaking around 25-30 kt, strongest across the inner waters north of Cape Falcon. A Small Craft Advisory is in effect for coastal waters north of Cape Foulweather, including the Columbia River Bar where a strong ebb current is expected this evening. Winds are expected to abruptly shift to the northwest behind the cold front as is moves across the waters later Tue afternoon and evening. Once the front passes, northerly winds return Tuesday night through the middle of the week. Another weak system may approach the northern waters from the west on Thursday, but likely remains north as it moves toward the Washington coast. A mid-period west-northwesterly swell of 6 to 8 ft at 13-15 seconds will move through the coastal waters today through Tue night, increasing significant wave heights into the 8 to 10 ft range. Seas then gradually subside to around 4 to 6 ft later in the week. /DH && .PQR WATCHES/WARNINGS/ADVISORIES... OR...None. WA...None. PZ...Small Craft Advisory from 5 PM this afternoon to 5 PM PDT Tuesday for PZZ210. Small Craft Advisory from 8 PM this evening to 5 PM PDT Tuesday for PZZ251-271. Small Craft Advisory from 5 AM to 5 PM PDT Tuesday for PZZ252- 272. && $$ www.weather.gov/portland Interact with us via social media: www.facebook.com/NWSPortland x.com/NWSPortland

720 FXUS66 KMFR 281746 AFDMFR Area Forecast Discussion National Weather Service Medford OR 1046 AM PDT Mon Sep 28 2026 ...New Aviation Section... .AVIATION (18Z TAFs)... A few hours of low ceilings and IFR conditions are expected at KOTH, but expecting relief this afternoon with clearing and VFR conditions. Inland TAF sites, are expected to experience plenty of sunshine today and mostly clear skies through this cycle. Otherwise, typical diurnal breezes expected across the area. && .PREV DISCUSSION... /Issued 441 AM PDT Mon Sep 28 2026/ KEY MESSAGES... * Warm and dry weather is expected through the week ahead. Temperatures peak on Thursday for the week, with additional warming possible on Saturday and Sunday. * In general, daytime highs look to be about 10 degrees above normal at their warmest. Shorter days and longer nights prevent any kind of hazardous warmth in this forecast period. DISCUSSION...A few stray showers drifting outside of the CWA are the last signs of activity early this morning. With the upper trough drifting off to the east, a Pacific ridge looks to guide conditions through much of the forecast period. The ridge axis starts over the ocean, which will bring some warming today but daytime highs will stay just below seasonal norms. Highs look to reach those norms on Tuesday, with mid 70s to low 80s west of the Cascades and mid 70s to the east. The warming trend continues through at least Thursday, which looks to have the warmest temperatures of the week as the ridge moves over the area. Coastal areas warm to the mid 70s while most west side valleys look to be in the mid to high 80s (The Umpqua Valley stays a little cooler). East side areas may cross into the low 80s. A shortwave trough moving over Washington state may prevent additional warming on Friday. With current deterministic imagery showing that minor disturbance moving eastward, the current forecast shows warming resuming into the weekend. Most areas could be 10 degrees above normal over the weekend. NBM probabilistic data has a 30-40% chance for the Rogue and Illinois valleys to reach 90 degrees on Saturday. Those chances rise to 40-50% on Sunday. Valleys and basins east of the Cascades have similar chances to see daytime highs over 80 degrees by Sunday. Long-term meteograms offer little hope of active weather through the forecast period, with precipitation basically absent from ensemble members across both the ECMWF and GFS into early October. At most, there are some minor fluctuations in how warm temperatures will get depending on how the ridge behaves. Fortunately, shorter days and longer nights prevent any sort of hazardous warmth during this warming period. -TAD AVIATION...28/12Z TAFs...MVFR to IFR ceilings remain at the coast, but lower flight levels look unlikely early this morning. Marine stratus looks to clear through the day, bringing VFR levels to coastal areas before MVFR/IFR levels possibly return tonight. Stable atmospheric conditions will allow inland areas will stay at VFR levels with normal diurnal breezes through the TAF period. MARINE...Updated 300 AM PDT Monday, September 28, 2026... A thermal trough pattern will keep gusty north winds and steep wind- driven seas over all coastal waters through today, with very steep seas south of Port Orford into this evening. Conditions gradually improve tonight into Tuesday morning. After a brief period of lower winds and seas Tuesday, the thermal trough could re- strengthen Wednesday into Thursday. && .MFR WATCHES/WARNINGS/ADVISORIES... OR...CA...None. PACIFIC COASTAL WATERS...Small Craft Advisory until 11 AM PDT Tuesday for PZZ356-376. Small Craft Advisory until 8 PM PDT this evening for PZZ350-370. Hazardous Seas Warning until 8 PM PDT this evening for PZZ356- 376. && $$

969 FXUS66 KEKA 282138 AFDEKA AREA FORECAST DISCUSSION National Weather Service Eureka CA 238 PM PDT Mon Sep 28 2026 .KEY MESSAGES... * High pressure builds through the rest of the week, bringing an extended dry period with interior valley high temperatures warming into the 80s and 90s. * An arriving long-period west-northwest swell brings an elevated risk for sneaker waves along beaches today. && .SYNOPSIS...Upper-level ridging builds over the West Coast this week, supporting a progressive inland warming trend and dry conditions through this coming weekend. && .DISCUSSION...Broad mid-level ridging over the eastern Pacific will expand inland Tuesday through Friday, establishing high confidence in dry conditions across the region. At the surface, the onshore pressure gradient between the offshore eastern Pacific high and the interior thermal low will drive fresh northerly winds along shore, strongest south of Cape Mendocino. Additionally, conditions will be gusty for many locations across Northwest California. Gusts greater than 20 mph could be possible this afternoon/evening and tomorrow afternoon/evening with an 80% chance or higher for coastal areas from Del Norte to Mendocino, and more widespread chances for all of southern Humboldt and most of Mendocino and Lake counties, and for the ridges of Del Norte and Trinity counties. There is an 80 percent chance or higher for gusts over 25 mph today and tomorrow for all coastal areas along with the King Range, with more widespread chances for Tuesday afternoon/evening. Strong atmospheric sinking beneath the upper ridge will steadily warm the air mass aloft. Thermal profiles across interior valleys will support afternoon maximum temperatures climbing into the 80s and 90s mid-week. Ensemble guidance highlights an 80% probability of interior valley highs exceeding 90F Wednesday and Thursday. && .AVIATION...Coastal stratus has cleared for coastal terminals this afternoon. Gusty northerly winds are likely this afternoon with gusts to 25 knots possible. General offshore flow aloft overnight could help stave off marine stratus development; however, light surface winds at the terminals could aid in stratus development. Gusty conditions are also probable for interior terminals this afternoon with general VFR conditions prevailing through the TAF period. Due to an ongoing ASOS communications outage at KUKI, automated observations are unavailable and amendments are not scheduled. && .MARINE...Fresh northerlies continue due to the pressure gradient between offshore high pressure and the interior thermal trough. * Northern Inner Waters: Northerlies of 10 to 20 kt will generate steep short-period seas. A west-northwest swell at 15 to 17 seconds arrives today. A Small Craft Advisory remains in effect through Tuesday morning. * Northern Outer Waters: Northerlies of 20 to 25 kt with gusts to 35 kt (mainly in the lee of Cape Blanco) will build combined seas to 10 to 11 ft. A Small Craft Advisory remains active through Tuesday morning. * Southern Inner Waters: Fresh to strong northwest winds of 20 to 25 kt with gusts to 35 kt (mainly in the lee of Cape Mendocino) will maintain steep seas. A Small Craft Advisory remains in effect through Tuesday morning. * Southern Outer Waters: Gale force conditions develop in the lee of Cape Mendocino, where northerly winds of 25 to 30 kt with gusts up to 40 kt will yield steep, hazardous combined seas of 11 to 12 ft. A Gale Warning remains in effect this afternoon through Wednesday morning. && .BEACH HAZARDS...A long period west northwest swell at 3 to 6 ft with a period up to 17 seconds will build in today. This swell will bring a moderate risk for sneaker waves. A smaller 3 ft long period south swell will also bring some risk for sneaker waves for south facing beaches. High astronomical tides will increase the danger, especially over rocks and jetties. Sneaker waves are a unique hazard, with up to 30 minutes between waves. Large, unexpected waves can sweep across the beach without warning, sweeping people into the sea from rocks, jetties, and beaches. These sneaker waves can also move large objects such as logs, crushing anyone caught underneath. Even ankle to knee deep water can knock you down and drag you out when a sneaker wave hits. Pay attention and stay above the high water line and any wet sand to stay safe. If the ground is wet, waves have surged. && .EKA WATCHES/WARNINGS/ADVISORIES... CA... None. NORTHWEST CALIFORNIA COASTAL WATERS... Small Craft Advisory until 9 AM PDT Tuesday for PZZ450-470. Small Craft Advisory until 9 AM PDT Wednesday for PZZ455. Small Craft Advisory until 3 PM PDT this afternoon for PZZ475. Gale Warning until 9 AM PDT Wednesday for PZZ475. && $$ 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

119 FXUS66 KMTR 281906 AFDMTR Area Forecast Discussion National Weather Service San Francisco CA 1206 PM PDT Mon Sep 28 2026 ...New SHORT TERM, LONG TERM... .KEY MESSAGES... Updated at 1205 PM PDT Mon Sep 28 2026 - Elevated fire weather conditions across the higher terrain through Wednesday - Areas of moderate HeatRisk across the interior Wednesday through Sunday - Minor coastal flooding for bayshore locations along the San Francisco, San Pablo, and Monterey Bays today through Friday && .SHORT TERM... Issued at 1205 PM PDT Mon Sep 28 2026 (This evening through Tuesday night) The stratus has largely cleared out with some isolated patches continuing at the immediate coast. Probability of stratus development tonight is low to very low, as incoming ridging and offshore flow will generally disrupt the marine layer stratus formation processes. The latest water vapor imagery shows an upper level low tracking across the southern Central Valley into the Mojave Desert, expected to continue trekking southeastward through the day and entering Arizona by Tuesday morning. Behind the low, an incoming ridge kickstarts a warming trend that will extend through the next couple of days. Today`s high temperatures range from the middle 70s to middle 80s inland to the upper 60s to middle 70s along the Bays and the lower to middle 60s at the Pacific coast. On Tuesday, high temperatures will reach the middle 80s to middle 90s inland, the middle 70s to middle 80s along the Bays, and the middle 60s to lower 70s at the Pacific coast. With the northerly flow aloft as the upper level low moves towards the southeast, a push of offshore wind is expected in the higher elevations Tuesday morning. Gusts of 25 to 35 mph are expected along the exposed ridgelines, and stronger gusts are possible along the ridge of the Vaca Mountains along the Napa-Yolo and Napa-Solano county lines. Elsewhere, generally diurnal winds will prevail with onshore winds developing each afternoon and evening, with gusts to 30 mph along the coast, through favored gaps and passes, and within the Salinas Valley. Minor coastal flooding is possible across the bayshore locations of San Francisco Bay, San Pablo Bay, and Monterey Bay around high tide starting today. Up to 1.2 feet of inundation above normally dry land is expected, including up to 0.6 ft of surge caused by thermal expansion and sea level rise since the sea level datum (basically the point where we define as "sea level") was set in the 1983-2011 period. At the San Francisco tidal gauge, high tide is expected to be 1.0 ft above normal (6.87 ft MLLW) at 12:57 PM Monday 9/28 and 1.2 ft above normal (7.01 ft MHHW) at 1:30 PM Tuesday 9/29. && .LONG TERM... Issued at 1205 PM PDT Mon Sep 28 2026 (Wednesday through next Sunday) There is an additional push of higher elevation offshore flow on Wednesday morning. This push will be more focused on the interior mountains of the North and East Bay with gusts a little lighter than those expected on Tuesday morning. Otherwise, temperatures may fluctuate by a few degrees each day, most notably on Thursday when stronger onshore flow will cause some of the coastal regions to dip by a few degrees, but the general trend should remain similar to Tuesday`s highs through the end of the seven day outlook. Areas of Moderate HeatRisk, a level of heat that brings a moderate risk of heat-related illnesses to sensitive populations, develop across the interior regions Wednesday through Saturday, but confidence in widespread impacts is not high enough to issue a Heat Advisory at this point. Longer-range guidance suggests that temperatures above the seasonal average will continue into the second week of October. Minor coastal flooding around high tide continues in low-lying areas across the San Francisco, San Pablo, and Monterey Bay shorelines through Thursday and potentially into Friday. At the San Francisco tidal gauge, high tide is expected to be 1.2 ft above normal (7.03 ft MHHW) at 2:10 PM Wednesday 9/30, and 1.1 ft above normal (6.92 ft MHHW) at 2:58 PM on Thursday 10/1. && .AVIATION... (18Z TAFS) Issued at 1026 AM PDT Mon Sep 28 2026 Marine layer impacts begin to fade 17-18Z as cigs/fog are thinning. Expect VFR this afternoon and most of tonight. Some CIGs will be possible late tonight around Monterey Bay. Less than 25% chc for fg at KSTS, but conf wasn`t high enough to include it in the TAF. Vicinity of SFO...Morning stratus has quickly faded and yielded VFR conditions. Will keep VFR through the rest of the TAF pd. NE flow will linger this morning before switching onshore this afternoon with higher gusts. SFO Bridge Approach...Similar to SFO. Monterey Bay Terminals...VFR this afternoon. CIGs return at MRY overnight, but conf is too low to include CIGs at SNS. Will carry a SCT group for clouds. && .MARINE... (Today through Saturday) Issued at 1026 AM PDT Mon Sep 28 2026 High pressure strengthening over the Eastern Pacific will maintain moderate to strong northerly breezes through Wednesday. Strongest winds will be outer water north of Point Reyes and the Big Sur Coast. Rough seas will build in response to these winds and will subside to moderate by the end of the week due to northerly winds becoming light to moderate. Tropical activity will produce long period swell up to 16 seconds Wednesday and Thursday. && .FIRE WEATHER... Issued at 515 AM PDT Mon Sep 28 2026 The marine layer persists this morning, around 1500-2000ft, but should gradually compress to around 500ft throughout the day. Today will be coolest day of the week, though it is also the start of a warming trend. Offshore flow gradually works its way into the region today, which will lead to breezy winds each morning from through Wednesday. The strongest winds are expected on Tuesday morning in the interior mountains of the North and East Bays, where wind gusts could reach 30-35 mph. These offshore winds should contribute to poor overnight humidity recoveries, with overnight relative humidities as low as 20-40% above the marine layer. && .MTR WATCHES/WARNINGS/ADVISORIES... CA...Coastal Flood Advisory until 5 PM PDT Thursday for CAZ006-506- 508-529-530. PZ...Small Craft Advisory until 3 AM PDT Wednesday for Pt Arena to Pt Reyes 0-10 nm. Small Craft Advisory until 9 PM PDT this evening for Pigeon Pt to Pt Pinos 0-10 nm. Small Craft Advisory until 11 PM PDT this evening for Pt Pinos to Pt Piedras Blancas 0-10 nm. Small Craft Advisory until 3 PM PDT Wednesday for Pigeon Pt to Pt Pinos 10-60 NM-Pt Arena to Pt Reyes 10-60 NM. && $$ SHORT TERM...DialH LONG TERM....DialH AVIATION...MM MARINE...MM 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

197 FXUS66 KOTX 282011 AFDOTX Area Forecast Discussion National Weather Service Spokane WA 111 PM PDT Mon Sep 28 2026 .KEY MESSAGES... - Breezy west to southwest winds may result in patchy blowing dust near recently plowed fields Tuesday afternoon. - Mild and dry pattern this week, except for rain near the Cascade crest and chance of rain North Idaho Panhandle on Tuesday. && .SYNOPSIS... Moisture off the Pacific will bring rain to the Cascade crest and northeast Washington and north Idaho mountains on Tuesday. Breezy west to southwest winds may result in patchy blowing dust near recently plowed fields Tuesday afternoon. Temperatures will be near normal through the middle the middle of the week and then trend to above normal for the end of the week and into the weekend. && .DISCUSSION... Monday night through Tuesday: : Weak troughing over the Inland Northwest will depart eastward today, transitioning to zonal flow aloft over the Pacific Northwest tonight. A frontal system moving into northern British Columbia will direct a moisture plume into the Washington Cascades, supported by a 120-125 kt upper-level jet streak positioned north of the international border. This setup favors orographically driven precipitation developing along the Cascades early Tuesday, spreading into northeast Washington and north Idaho mountains Tuesday afternoon. Precipitation amounts will be maximized across the west slopes of the Cascades and at the Cascade crest with high confidence (greater than an 80% chance) for amounts exceeding 0.50 inches. Strong westerly flow aloft into the Cascades will produce a pronounced rain shadow east of the crest, with amounts quickly dropping off farther east. Precipitation amounts will be much lighter across northeast Washington with a 50% chance for 0.10 inches of rain across the northern Selkirks and a 25% chance as far south as Mount Spokane. Winds will also be breezy on Tuesday as 850mb winds increase to 20- 30 knots. The Inland Northwest will be within the warm sector with the boundary layer only mixing up to around 800mb Tuesday afternoon. This will limit the stronger winds at 700mb to materialize down to the surface. Despite lower mixing heights, the National Blend of Models shows a 60-80% chance for wind gusts greater than 30 mph across the Columbia Basin into the Spokane West Plains Tuesday afternoon. These gusts may result in patchy blowing dust near recently plowed fields. Wednesday through Sunday: A warming trend is anticipated as ensemble guidance depicts an upper-level ridge amplifying across the western US. Uncertainty exists Thursday into Friday regarding the northward extent of the ridge axis. Approximately 45% of ensemble members favor persistent zonal flow, which would direct another moisture plume into the Pacific Northwest with an additional period of light mountain precipitation. The remaining 55% of members build the ridge more aggressively over the region, supporting a drier solution. Ensembles are in better consensus for the upper-level ridge to become established over the western US this weekend, resulting in warm and dry conditions across the Inland Northwest. /vmt && .AVIATION... 18Z TAFS: Clear skies will give way to increasing high cirrus this afternoon then mid and high clouds after 04z with the arrival of moisten laden westerly 500mb jet. Surface winds today will be light through the morning with a subtle increase from the south/southwest, especially across the Columbia Basin and Okanogan Valley. The strong westerly flow across the Cascades tonight into Tuesday will promote lee waves and favorable pattern for turbulence with gusty winds surfacing in the lowlands by Tuesday afternoon. The Cascade crest will likely experience widespread mtn obscurations Tuesday as well with steady precipitaiton. /sb FORECAST CONFIDENCE AND/OR ALTERNATE SCENARIOS: High confidence for VFR conditions at all TAF sites today. ----------------------- 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 45 67 47 68 45 69 / 0 10 10 0 0 0 Coeur d`Alene 43 63 48 65 45 67 / 0 10 10 0 0 10 Pullman 42 66 46 65 43 69 / 0 0 10 0 0 0 Lewiston 46 74 53 71 49 74 / 0 0 0 10 0 0 Colville 41 66 38 67 36 69 / 10 20 10 0 0 10 Sandpoint 41 61 44 64 41 65 / 0 30 20 10 0 10 Kellogg 42 61 48 63 45 67 / 0 10 30 20 0 10 Moses Lake 46 73 47 71 44 73 / 0 10 0 0 0 0 Wenatchee 50 69 51 69 52 70 / 10 20 10 0 0 0 Omak 48 67 43 69 45 70 / 0 10 10 0 0 0 && .OTX WATCHES/WARNINGS/ADVISORIES... WA...None. ID...None. && $$

136 FXUS66 KPDT 282135 AFDPDT Area Forecast Discussion National Weather Service Pendleton OR 235 PM PDT Mon Sep 28 2026 .KEY MESSAGES... - Light to moderate rain showers (70-90% chance) along the Cascade Mountains on the Washington side, with lighter amounts along the Northern Blue Mountains. - Breezy winds develop across the Cascade gaps and other parts of the Basin. - Temperatures will be near to slightly above normal throughout the week. && .DISCUSSION... Very little activity with satellite and radar currently as zonal flow currently dominants aloft. Overnight freezing was present in parts of Central Oregon and the Wallowa`s, we may see a second round of some freezing although confidence is lower this time around (10-20% chance) as winds are stronger tonight compared to last night. Given that, I`m not expecting freezing temperatures, if any, will last enough to warrant freeze warnings tonight. Our next weather maker and cold frontal system is around the corner, but will mostly impact the mountain regions and parts of the Foothills of the Blues to a lesser extent. A trough/shortwave located in the Pacific and British Colombia will move along the area, bringing light to moderate rain showers in the Washington Cascades (70-90% chance), Northern Blue Mountains (20-40% chance), and parts of the Foothills of the Blues (up to 20% chance). Guidance makes it pretty clear that parts of the Cascade region near Snoqualmie (and the Three Queens fire) will see wetting rains develop over the 24-48 hours. It`s keyed in that region will see at least a tenth of an inch of rain (>90% chance), while seeing a quarter of an inch is also very likely (75-85% chance). Current NBM guidance advertises nearly an inch close to Snoqualmie pass while it quickly drops off the further away from the peaks you are. The secondary maximum of QPF is located in the Northern Blue mountains with only up to a tenth of an inch advertised (50-70% chance). While Snoqualmie could get up to an inch, it`s unlikely we`ll see any widespread flooding (even on burn scars) happening, although the chance for localized flooding in flood prone areas is not out of the question. The front will also increase PG`s across the area, developing breezy to locally windy conditions across the area (especially near the Gaps and parts of the Basin). Wind gusts in the strongest areas could reach 30-40 mph (50-70% chance). Clusters struggle a bit trying to handle the strength of zonal flow ahead of a ridge pushing onshore. About 29% of clusters want to keep the zonal flow above the area, bringing additional light to moderate mountain showers. Something to monitor, but no big impacts are expected from this set-up with any QPF`s falling should be light to moderate (80-90% chance). Guidance paints the end of this week through next week as a ridge amplifying over the PacNW, bringing dry and warm conditions. Something to keep an eye out fire weather wise, but any impacts on RH`s and/or winds is a bit too far out to make any conclusions. && .AVIATION /18Z TAFS THROUGH 18Z TUESDAY/... VFR conditions prevail with dry and mostly clear conditions through the forecast period. Winds will be a bit elevated in the 7 to 12 knot range, with breezier conditions developing in the DLS by the afternoon. Otherwise, no CIG or VIS issues expected. && .Preliminary Point Temps/PoPs... PDT 45 75 49 72 / 0 0 0 0 ALW 52 75 54 73 / 0 0 10 0 PSC 47 78 50 75 / 0 0 0 0 YKM 48 74 49 71 / 0 10 0 0 HRI 49 77 51 75 / 0 0 0 0 ELN 45 66 46 66 / 0 20 20 0 RDM 37 75 39 74 / 0 0 0 0 LGD 41 75 46 71 / 0 0 10 10 GCD 40 75 43 74 / 0 0 0 0 DLS 50 73 54 76 / 0 0 10 0 && .PDT WATCHES/WARNINGS/ADVISORIES... WA...None. OR...None. && $$ DISCUSSION...95 AVIATION...95

597 FXUS65 KREV 282107 AFDREV Area Forecast Discussion National Weather Service Reno NV 207 PM PDT Mon Sep 28 2026 .KEY MESSAGES... * Low chances of light showers and isolated thunderstorms persist south of Interstate 80 through the afternoon. * A chilly Tuesday morning is expected for colder Sierra valleys, and along higher Sierra elevations where winds become gusty. * Dry weather prevails after today with temperatures warming to above average by midweek. && .DISCUSSION... Shower and thunderstorm activity continues to wind down as noted on latest radar obs, with only a few lingering showers in Mono County as of 2 PM PDT. This area will be the focus for additional showers and perhaps isolated thunderstorms through the midafternoon. Light snow showers also are possible along the higher peaks of the White Mountains and Sierra in far S Mono County before showers taper off by the late afternoon. The upper low responsible for today`s cool and showery weather will continue to track to the southeast, leaving north to northeast breezes in its wake. Winds will become gusty along and west of the Sierra crest tonight into early Tuesday morning with NE gusts around 40-50 mph. Tuesday morning is shaping up to be a chilly one for colder Sierra valleys as temperatures fall near or below freezing. Higher Sierra elevations will also be quite brisk early Tuesday morning as the aforementioned gusty NE winds make it feel colder than it really is. Be sure to bundle up if traveling or recreating in these areas Tuesday morning! High pressure begins to overspread the region after today, keeping the rest of the week and weekend dry. Temperatures will sharply increase through midweek, resulting in upper 70 to 80 degree highs from mid to late week. -Salas && .AVIATION... Isolated showers may occasionally lower CIGS/VIS to MVFR conditions at KMMH through 23z, otherwise VFR conditions and light north breezes prevail today. E-NE FL100 winds will increase to 25-30 kts overnight, which may lead to periods of mountain wave turbulence along and west of the Sierra crest between 03Z and 12Z. -Salas && .REV Watches/Warnings/Advisories... NV...None. CA...None. && $$

890 FXUS66 KSTO 281918 AFDSTO Area Forecast Discussion National Weather Service Sacramento CA 1218 PM PDT Mon Sep 28 2026 For additional details on weather and expected impacts over the next 7 days, please visit weather.gov/sto/briefing. .KEY MESSAGES... - Elevated fire weather conditions today-Thursday AM due to periods of breezy north to east winds and low humidities. - High temperatures, 5-15 degrees above normal, will lead to Moderate HeatRisk in the Delta and Valley/foothills south of I-80 Thursday-Sunday && .DISCUSSION... ...Today-Thursday AM (9/28-10/01)... Abundant sunshine is being observed across Northern California this afternoon via GOES satellite. High temperatures today will feel noticeably warmer compared to yesterday, with Valley highs in the mid to upper 80s. Periods of breezy northerly flow will continue through the Sacramento Valley today through Thursday AM as a trough closes off into a low and tracks southward and eastern Pacific ridging builds in to the north. These winds along with low humidity will bring elevated fire weather conditions to the Sacramento Valley and portions of the Sierra. Winds peak on Tuesday, and have trended a slightly stronger in the forecast, as the low pressure digs further southeast into SoCal/Desert Southwest. The resultant north to east winds are forecast to gust 15-25 mph in the Valley; 30-40 mph over the Sierra and the far western Sacramento Valley and eastern foothills of the Coast Range. While not the classic Inside Slider pattern, elevated fire weather conditions will increase Tuesday with further drying, with daytime humidity values forecast to be in the teens for the northern Sacramento Valley; 15-25% in the mountains. Additionally this will increase gap flow winds through the Coast Range and the eastern slopes of the Diablo Range, especially into Tracy. Valley winds weaken on Wednesday, but will remain gusty over the Sierra and through gaps and canyons into Thursday morning. ...Thursday(rest of)-Sunday (10/01-10/04)... High temperatures will increase significantly by Wednesday/Thursday as ridging builds overhead and the low treks further east. High temperatures will climb 5 to 15 degrees above normal Thursday through Sunday. As a result, Moderate HeatRisk is expected across the northern San Joaquin, southern Sacramento Valley, the Motherlode, and Delta. Winds will remain light, minimizing relief from the warm temps. No precipitation is expected over the next several days at this time. Take extra precautions against heat-related illnesses! If you`re spending long periods of time outside this week into the weekend, remember to stay hydrated, wear breathable clothing, and try to take breaks in the shade. && .AVIATION... VFR conditions prevail across interior NorCal next 24 hours. Periods locally breezy north surface wind gusts thru 02z Tuesday in the Valley, with gusts up to 25 kts. Mountain wind gusts generally below 15 kts next 24 hours. && .STO WATCHES/WARNINGS/ADVISORIES... None. && $$

074 FXUS65 KMSO 281909 AFDMSO Area Forecast Discussion National Weather Service Missoula MT 109 PM MDT Mon Sep 28 2026 .DISCUSSION... KEY MESSAGES: - Near-normal temperatures with the weather pattern during this week, along with mostly dry conditions. - Increasing winds Tuesday, especially across northwest Montana and the higher terrain. - Scattered rain showers Tuesday night into early Wednesday then slight warming trend into the remainder of the week. - Confidence increasing for a warmer and drier than normal early October beyond the 7 day forecast. Valley inversions in September today started with weak valley inversions which may keep realization of peak warming subdued and hold off afternoon breezes until late afternoon. Tuesday as a weak wave moves through the region, breezy conditions are expected to develop. Strongest winds will be north of I-90 and in the mountains but valleys of northwest MT could easily see gusts into the 20s on Tuesday. Due to winds developing early lake recreationalists will be less likely to be surprised during the afternoon. That said, prepare for choppy conditions on area lakes. Overnight into Wednesday a few showers develop, mainly along the Idaho/ Montana border and in Glacier National Park. These showers will be light in nature and the probability of a wetting rain, or greater than 1/10 of an inch, is 40 to 60% in the highest terrain. Most valleys, with the elevated winds even overnight, will see increased effects of downsloping. Longer term the models have been very consistent is demonstrating a building ridge of high pressure. This outcome is common in the fall but temperatures in the National Blend of Models are forecast to be 10 to 15 degrees above normal. The reason this discussion began with `valley inversions` is because, depending if valley inversions develop and their strength, high temperature forecasts may be difficult for the start to October. Current models predict for the ridge axis to be west of the Rockies, which would assist in the development of valley inversions. Additionally, Pacific tropical activity could throw a wrench into longer term forecasts, causing more variation in the pattern or exciting ridge breakdowns, more to come. && .AVIATION...VFR conditions will dominate into Tuesday with light, diurnally driven winds. Westerly winds will pick up on Tuesday late morning/early afternoon, and a weakening moisture plume will bring some showers to the terrain of northwest Montana late in the day. && .MSO WATCHES/WARNINGS/ADVISORIES... MT...None. ID...None. && $$

263 FXUS65 KBOI 281957 AFDBOI Area Forecast Discussion National Weather Service Boise ID 157 PM MDT Mon Sep 28 2026 .KEY MESSAGES... - Breezy northwest winds in the Snake Plain each afternoon through Wednesday. - Fair skies and warmer temperatures through this weekend. && .SHORT TERM /Through Wednesday Night/... As a trough moves east, high pressure builds to the south of our forecast area. Zonal flow will cap off the high pressure, leading to a moderated warming trend up to about 5 degrees above normal in the short term. Dry/fair weather is expected through the period, as moisture in the flow is positioned along the Canada-US border. West to northwest surface winds will become breezy each afternoon in the Snake Plain, especially between Boise and Twin Falls. The breezy 20-30 mph peak wind gusts occur in an area where forecast minimum relative humidities are around 15-20%, creating elevated fire weather though in a very localized portion of the high desert. Surface winds begin to taper off heading into the long term forecast. && .LONG TERM /Thursday through Monday/... The area will remain under a flattened ridge north of a massive Pacific high slowly building into the Great Basin region. This continuous ridging pattern will favor clear skies, dry conditions, and the return of warmer than normal temperatures Thursday through Friday. A weak shortwave trough passing north of our area late Friday may bring in some high cloud coverage, possibly moderating the daytime temperatures on Saturday. Otherwise, broad Pacific ridging will dominate the region Sunday through early next week, continuing a much warmer and drier than normal pattern in the extended outlook. && .AVIATION /18Z Monday through Tuesday/... Issued 1153 AM MDT MON SEP 28 2026 VFR with clearing skies this afternoon through tonight. Patchy morning fog/low stratus in sheltered mountain valleys Tuesday morning. Surface winds: W-NW 5-15 kt, afternoon gusts to 25 kt from KBOI to the south/east. Winds aloft at 10kft MSL: W-NW 5-15 kt. KBOI...VFR with clear skies. Surface winds: W-NW 4-10 kt, increasing to 10-15 kt with gusts to 20-25 kt this afternoon after 20Z, lowering to 6-11 kt in the evening after Tue/02Z. && .BOI WATCHES/WARNINGS/ADVISORIES... ID...None. OR...None. && $$ www.weather.gov/Boise Interact with us via social media: www.facebook.com/NWSBoise www.x.com/NWSBoise SHORT TERM...JM LONG TERM....JY AVIATION.....JY

721 FXUS65 KLKN 281637 AFDLKN Area Forecast Discussion National Weather Service Elko NV 937 AM PDT Mon Sep 28 2026 .KEY MESSAGES... * A few strong thunderstorms possible in Eastern Nevada this afternoon into this evening * Showers likely in East Central Nevada today * Warming trend Tuesday through Thursday * Unseasonably warm Friday and Saturday && .DISCUSSION... (This afternoon through Sunday) WEATHER PATTERN OVERVIEW: An upper-level area of low pressure will progress southward across California this afternoon. This cyclone aloft will pivot eastward and progress through Southern Nevada tonight. Rain chances will be highest in Southeastern White Pine County today and tonight. A few strong thunderstorms are conceivable in Eastern Nevada this afternoon into this evening. The primary thunderstorm hazards will be wind gusts near 50 mph and dangerous cloud to ground lightning strikes. A ridge of high pressure will build across Northern Nevada Tuesday through Thursday. An anticyclone aloft will be centered over Southern California Friday. This upper-level area of high pressure will move eastward across the Desert Southwest this weekend. A warming trend is expected Tuesday through Thursday. By Thursday afternoon, high temperatures in Northern and Central Nevada will be around ten degrees above normal. Temperatures will remain well above seasonal values Friday through Sunday. Here are probabilities of maximum temperatures of 80 degrees or higher for select locations in Northern and Central Nevada on Friday, October 2nd, 2026: Tonopah - 97% Elko - 95% Battle Mountain - 95% Carlin - 95% Eureka - 95% Winnemucca - 90% Ely - 90% Wells - 90% Spring Creek - 85% West Wendover - 80% FORECAST CONFIDENCE & DEVIATIONS: High forecast confidence regarding the possibility of a few strong thunderstorms in Eastern Nevada this afternoon into this evening. High forecast confidence in the likelihood of showers in East Central Nevada today. High forecast confidence regarding a warming trend Tuesday through Thursday. Moderate forecast confidence in temperatures remaining well above seasonal values Friday through Sunday. No deviations from the NBM model output. && .AVIATION... VFR conditions will prevail at all terminals through at least the next 24 hours. Showers, and perhaps a thunderstorm, will be in the vicinity of KELY, KENV, and KTPH this afternoon into tonight. Direct impact cannot be ruled out. && .FIRE WEATHER... A few strong thunderstorms are possible in Eastern Nevada this afternoon into this evening. The primary thunderstorm hazards will be erratic wind gusts near 50 mph and dangerous cloud to ground lightning strikes. A warming trend is expected Tuesday through Thursday. By Thursday afternoon, high temperatures will be around ten degrees above normal for this time of year. && .LKN Watches/Warnings/Advisories... None. && $$ 87