401 FXUS66 KSEW 271113 AFDSEW Area Forecast Discussion National Weather Service Seattle WA 315 AM PST Sat Dec 27 2025 .SYNOPSIS... Persistent snow showers will continue over portions of the Cascades this morning while some morning mixed precipitation may be possible as post frontal showers linger over portions of western Washington. High pressure begins to build over the area today, drying conditions out but allowing for colder overnight temperatures and likely fog development each morning into early next week. A return to a more typical pattern of lowland rain and mountain snow is expected late in the upcoming week. && .SHORT TERM /TODAY THROUGH MONDAY/... The main focus this early morning is with two PSCZs...one stretching southeastward from southwester Whatcom county down into northeaster Snohomish county and the other stretching from Port Angeles into east central King county. The combination of these two bands of precip are keeping snow showers active over the Cascades. Latest radar trends do not really indicate much of a slowing down, so will opt to extend current Winter Weather Advisory for the Cascades for another 6 hours to cover this continuing activity. As for mixed precip, lowland locations in the path of precip associated with these PCSZs may find some scattered flakes mixed in with showers, however no significant accumulations are expected. Looking elsewhere in the CWA, there are some lingering post-frontal showers over southwestern portions of the area, but temperatures there remain mostly warm enough to keep anything that falls as liquid. Models remain consistent drying things out over W WA as upper level ridging starts to build into the area. A weak impulse along the leading edge of this feature could allow for a slight chance for precip this evening and early tonight...and temps could be just low enough to allow perhaps some flakes mixed in with any showers that develop. Otherwise, the main risk tonight and for the remainder of the short term will be overnight fog development and low temps generally in the lower 30s. Guidance suggests the best chances for near or slightly below freezing temps being tonight with slightly warmer temps expected Sunday night and Monday night...turning the tables in favor or near to slightly above freezing temps. Any areas still recovering from recent floods that may not have re-insulated plumbing and such may need to take measures against these colder temps. While this is more of an isolated concerns for much of the CWA, the prospect of some east to northeasterly winds, perhaps with some Fraser influence, poses an increased risk of overnight lows tonight getting into the upper 20s. Will need to continue to monitor conditions to see if further cold weather headlines will be needed up that way. 18 && .LONG TERM /TUESDAY THROUGH FRIDAY/... Models start to flatten out the ridge as the ridge axis moves further eastward Tuesday night. If anything, the switch to more southwesterly flow aloft will partner with onshore flow to help give overnight lows a nudge upward into the mid to upper 30s by mid-week. Deterministic models have shifted away from bringing the next frontal system into the area Wednesday, opting instead to delay this feature until late Thursday night/early Friday. Ensembles, however, remain consistent with their solutions, opting to bring this feature in late Wednesday afternoon/early Wednesday evening. Once the front enters the area, however, W WA will return to a more active pattern as a series of features pass through the area at the end of next week and into the new year. 18 && .AVIATION... Upper level trough east of the area early this morning with northwesterly flow aloft. Weak system embedded in the flow aloft moving over the area tonight. Upper level ridge building along the coast Sunday. In the lower levels light onshore flow with weak Fraser river outflow over Whatcom county this morning. Low level flow becoming northerly all areas this afternoon and evening. Convergence zone near KPAE dissipating 12z-15z. Real mixed bag this morning with multiple scattered to broken layers between 2000 and 6000 feet. 2000 foot deck dissipating midday with VFR conditions this afternoon into tonight. Patchy fog developing over the Southwest Interior and Kitsap Peninsula Sunday morning. KSEA...MVFR ceilings at times this morning with VFR conditions this afternoon into Sunday morning. Patchy fog/low stratus in the vicinity of the terminal 13z-18z Sunday. Southerly wind 4 to 8 knots becoming northerly around 19z. Felton && .MARINE... High pressure will build over the waters today and remain situated across the area through early next week. The ridge will weaken Wednesday as a front approaches the area. Small craft advisory winds over the coastal waters will ease later this afternoon. Small craft advisory winds also over the Northern Inland Waters with weak Fraser river outflow easing as well later this afternoon. Seas in the 10 to 13 foot range today subsiding under 10 feet tonight. Seas remaining 6 to 9 feet later tonight into the first part of next week. Light winds Sunday through Tuesday for possible dense fog formation in the late night and early morning hours. Felton && .HYDROLOGY... No river flooding in the next 7 days. && .SEW WATCHES/WARNINGS/ADVISORIES... WA...Winter Weather Advisory until 10 AM PST this morning for Cascades of Pierce and Lewis Counties-Cascades of Snohomish and Northern King Counties-Cascades of Southern King County-Cascades of Whatcom and Skagit Counties. Cold Weather Advisory until noon PST today for Lowlands of Western Whatcom County. PZ...Small Craft Advisory until 6 PM PST this evening 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-Grays Harbor Bar. Small Craft Advisory until 2 PM PST this afternoon for Northern Inland Waters Including The San Juan Islands. && $$

144 FXUS66 KPQR 271055 AAA AFDPQR Area Forecast Discussion...UPDATED National Weather Service Portland OR 254 AM PST Sat Dec 27 2025 .SYNOPSIS...A weak frontal system continues to slowly move eastward across the Cascades and out of the region. This is resulting in diminishing showers and snow showers to the mountains through this evening. A ridge of high pressure builds towards the end of Saturday and through Sunday. This will bring dry and cool conditions to the forecast area and this pattern is expected to persist through at least the middle of this week. && .SHORT TERM...Now through Tuesday Night...Current radar imagery shows diminishing showers across the CWA this morning. Cold air and diminsihing showers are resulting in snow continuing to accumulate at elevations above 4000 ft. Will maintain the current Winter Weather Advisory through at least this afternoon as precipitation is expected to cease by then. As Saturday night/Sunday morning approaches, a ridge of high pressure is expected to build in over the CWA. This will bring cold and dry conditions into the forecast, which are expected to persist through at least Wednesday. Afterwards, a pattern change is expected, but there remains some uncertainty as to the timing of the system for the latter part of the week. Focusing on today through Tuesday, there are two forecast challenges to address. The first is the overnight temperatures. Models continue to lower the overnight temperatures with increasing probability in temperatures at or below freezing within the lowlands starting tonight through Tuesday night. At this time, the coldest overnight time frame looks to be tonight into Sunday morning. The coldest areas will be the central and southern Willamette Valley as well as the rural areas of the interior lowlands, with around a 40-80% probability of overnight low temperatures of 32 degrees F and a 5-10% probability of overnight lows at or below 29 degrees F. The second factor to consider will be the presence of fog and or frost. At this point, frost appears to be the most likely scenario due to the lack of saturation but cannot rule out areas of fog. /42 .LONG TERM...Wednesday through Friday...Cold weather persists through at least Wednesday as high pressure lingers. As we move into Thursday, the forecast gets a bit more complicated. Models maintain an upper level ridge over the region, while some ensembles suggest a broad, long wave trough moving into the region that will bring precipitation and slightly warmer air. This particular set-up is resulting in a moderate PoP/low QPF scenario. It should be noted that confidence in the forecast is low with the variety of solutions being produced by the models and their ensembles. So, we will continue to monitor the situation and see what the first part of 2026 brings to the Pac NW. /42 && .AVIATION...Radar imagery and terminal observations as of early this morning show lingering showers with predominately VFR conditions across the airspace. West-northwest winds around 5 to 10 kt through the TAF period. After 04Z Sunday, increasing probability of MVFR conditions developing across the air space as a ridge of high pressure slowly builds over the Pac NW. Clearing skies, light winds and overnight lows are expected to fall at, near or just below freezing. This could result in frost development on elevated, metal surfaces starting around 06Z Sunday. After 10Z Sunday, could see isolated IFR conditions develop, with a 15-25% probability within the Willamette Valley. KPDX AND APPROACHES...Predominately VFR conditions with west- northwest winds around 5 to 10 kt through the TAF period. After 05Z Sunday, increasing probability of MVFR conditions. Clearing skies, light winds and overnight lows are expected to fall at, near or just below freezing. This could result in frost development on elevated, metal surfaces starting around 06Z Sunday. /42 && .MARINE...A post frontal environment continues to develop over the waters. Seas 10 to 15 ft at 10 to 12 sec across all waters, highest north of Cascade Head. A Hazardous Seas Warning remains in effect for all outer water zones and a Small Craft Advisory for all inner waters and the Columbia River Bar through at least Saturday afternoon for a combination of winds and seas. Winds and seas slowly subside, with conditions falling below Hazardous Seas and Small Craft thresholds by late this afternoon. A ridge of high pressure builds overhead this evening into Sunday. Winds decrease to less than 15 kts by this evening along with seas settling towards to 4 to 6 ft range. These conditions are expected to persist to persist into next week as high pressure builds over the waters. /42 && .PQR WATCHES/WARNINGS/ADVISORIES... OR...Winter Weather Advisory until 4 PM PST this afternoon for ORZ126>128. WA...Winter Weather Advisory until 4 PM PST this afternoon for WAZ211. PZ...Small Craft Advisory until 4 PM PST this afternoon for PZZ210- 251>253. Hazardous Seas Warning until 4 PM PST this afternoon for PZZ271>273. && $$ www.weather.gov/portland Interact with us via social media: www.facebook.com/NWSPortland x.com/NWSPortland

805 FXUS66 KMFR 271130 AFDMFR Area Forecast Discussion National Weather Service Medford OR 330 AM PST Sat Dec 27 2025 .UPDATE...Aviation Discussion Updated. && .AVIATION (12Z TAFs)... Light isolated to scattered showers will continue today, with activity mainly focused from the Southern Oregon Cascades west. Showers will taper off in the late afternoon. Low clouds and fog remain a concern for westside valleys this morning (KRBG and KMFR). Guidance supports MVFR develop early this morning at Roseburg and Medford with lower chances (15-25%) for LIFR/IFR in fog or low stratus. Given the mid and high clouds over the area along with weak shower activity, have leaned towards MVFR conditions developing at Medford and Roseburg this morning. Then, expect clearing to VFR in the late morning and early afternoon. Otherwise, expect VFR with areas of mountain obscurations. Then, high pressure moving into the region will bring stable conditions. Models and guidance support chances for valley fog and freezing fog developing with IFR/LIFR around 8-12z. These conditions are most likely for Roseburg and Medford. && .PREV DISCUSSION... /Issued 306 AM PST Sat Dec 27 2025/ DISCUSSION...A upper trough is over the region bringing a cool, unstable air mass today. This combined with moist onshore flow is allowing for mid level clouds and light rain and snow showers over the area. Showers will be most concentrated from the Southern Oregon Cascades west. Snow levels are around 2000-3000 feet and will rise slightly during the afternoon to 2500-3500 feet. Expect any snow showers to be light though with best chances for additional light snow accumulations (1-2 inches) over the Southern Oregon Cascades. Colder air will move into the region today resulting in high temperatures around 4-8 degrees cooler than yesterday. Showers will taper off tonight but cold air will linger. Tonight, expect overnight lows in the teens for valleys east of the Cascades, into the 20s for valleys in central and western Siskiyou County and in the upper 20s to lower 30s for valleys west of the southern Oregon Cascades. With high pressure moving in place, expect stable conditions overnight and Sunday morning with valley fog and freezing fog likely for many inland valleys. This may impact travel on area roads and airports. Temperatures will remain on the cool side on Sunday, with high temperatures near or slightly below normal. This pattern with stable and dry weather as well as chances for overnight/morning fog continues early next week. Temperatures will trend slightly warmer Monday into Tuesday. Then, models continue to point towards the ridge moving east of the area on Thursday with a most frontal system and trough moving into the region from the west and northwest. This will bring chances for precipitation (50-80%) to the area Thursday into Friday. Confidence is low on details for this period and model solutions continue to show significant variability on the track and strength of this next system. We will continue to monitor and update as details become clear. PREV EXTENDED DISCUSSION.../Issued 257 PM PST Fri Dec 26 2025/ The National Blend of Models(NBM) is forecasting the probability of precipitation to increase late Thursday into Friday. The probability of precipitation varies from 50 to 70 percent, which isn`t that bad this far out. Ensemble members appear to hint at an atmospheric river event, although it is very unclear if it will be an AR with strong southerly, westerly, or north westerly flow. None of the ensembles are bombing out a cyclone in our waters, so that is good news with regards to a potential wind event. In any case, it looks like more precipitation is on the way, but the elevation the snow will fall at is very much up in the air. MARINE...Updated 200 AM PST Saturday, December 27, 2025...Steep seas are expected across all waters through this evening. Seas may be locally very steep this morning for the waters north of Cape Blanco. Then, tonight into Sunday, northwest swell will gradually lower but expect gusty north winds and steep seas across the waters south of Cape Blanco beyond 10 nm from shore. Winds and seas are expected to ease early next week. && .MFR WATCHES/WARNINGS/ADVISORIES... OR...Winter Weather Advisory until 4 AM PST early this morning for ORZ027-028. CA...None. PACIFIC COASTAL WATERS...Small Craft Advisory until 10 PM PST this evening for PZZ350-356-370-376. && $$

862 FXUS66 KEKA 270821 AFDEKA AREA FORECAST DISCUSSION National Weather Service Eureka CA 1221 AM PST Sat Dec 27 2025 .SYNOPSIS...Drier and colder weather this weekend is expected to last into Tuesday. A frontal system will provide rain and high mountain snow around Thursday and Friday. && .DISCUSSION...Surface high pressure and ridging aloft will bring drier weather and clearer skies for the remainder of the weekend. Breezy northerlies along the North Coast are forecast to diminish tonight and become gusty from the E and NE over exposed ridges and mountain tops Saturday night. Morning frost and freezing temperatures are probable for coastal areas early Sunday morning as light east winds chase dewpoints down through the night. Arcata and McKinleyville have the highest chance (75-97%) for morning minimums of 32F or less. Eureka could freeze as well, but the chance is only 60% according NBM. A massive 500mb height anomaly will continue to dominate NW California weather early to mid next week and ensure dry/stable weather conditions. This weather pattern with warmer air aloft invariably results in nightly fog and low clouds in the interior valleys. Ridge aloft will begin to weaken around mid week as a trough from the Gulf of AK digs south and eastward. Chances for rain and mountain snow will begin to increase late week (Thu and Fri) as a surge of subtropical moisture associated with a frontal boundary spreads over the area from the SW. Chance for 1 inch or more of rain in 24 hours will increase to about 30-50%. Global ensembles are quite variable on the timing and amount of precipitation. It does appear to be a relatively short duration with low probability for IVT over 250 kg/m/s on Thu. Frontal passage may take until Friday when heavier precip rates appear more likely. && .AVIATION...Gusty coastal winds are coming to an end at CEC and ACV with light winds and generally cloudy conditions expected overnight. Ceilings are questionable as to how low they will become along the coast with low end VFR or MVFR expected. Farther inland, as skies clear, fog will likely develop due to all of the recent rainfall. Should the skies clear and fog develop at UKI then LIFR is likely in the morning hours. This fog will mix out in the late morning for most locations but some valleys could see fog linger into the afternoon. At the coast any low cloud will quickly dissipate leaving VFR. Gusty northwest winds may return for the afternoon at the coast. /RPA && .MARINE...Winds and seas will gradually subside over the next 24-36 hours or so as the area of low pressure that has been impacting our region with strong southerly winds moves out the area. Northerlies have developed across the waters as high pressure builds over the eastern Pacific. Gusty winds of small craft to near gale will be possible over the next 24 hours before the pressure gradient weakens and light offshore winds develop late in the weekend into early next week. Steep seas will subside in response and a period of relatively tranquil conditions will develop across the coastal waters for early to mid week. The next storm system will approach Wednesday into Thursday with light southerlies redeveloping. Model guidance at this time indicates winds should not become too strong with this next system. /RPA && .COASTAL FLOODING...Chance for salt water inundation of normally dry areas will increase each day for the Humboldt Bay area during high astronomical tides each day next week. && .EKA WATCHES/WARNINGS/ADVISORIES... CA...None NORTHWEST CALIFORNIA COASTAL WATERS... Small Craft Advisory until 3 AM PST Sunday for PZZ450. Gale Warning until midnight PST tonight for PZZ455-475. Small Craft Advisory until noon PST Sunday for PZZ455. Small Craft Advisory until 11 AM PST Sunday for PZZ470. Small Craft Advisory until 6 PM PST Sunday 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

645 FXUS66 KMTR 271200 AFDMTR Area Forecast Discussion National Weather Service San Francisco CA 400 AM PST Sat Dec 27 2025 ...New SHORT TERM, LONG TERM... .KEY MESSAGES... Updated at 359 AM PST Sat Dec 27 2025 - High pressure builds in with dry weather on through early to mid next week. - Cold overnight lows through early next week.&& .SHORT TERM... Issued at 359 AM PST Sat Dec 27 2025 (Today and tonight) Upper level ridging builds to our east, pushing the upper level trough off to our west. THis will usher in drier weather to the region with most lingering showers being cut off by morning. Cooler weather is on tap with high temperatures chilling in the low to mid 50s for many valley and coastal communities, while mountainous regions vary from the low 40s to the mid 50s. Tonight, temperatures are expected to be cold as well. The question will be, do we get some high clouds skirting across the Bay Area counties? Should that happen temperatures might be a few degrees warmer than forecast. Should it not happen, we could be a few degrees colder due to radiational cooling. That would fall more inline with the some of the MOS guidance. Farther to the south, mostly clear skies should prevail with temperatures for the interior Central Coast falling into the 30s, perhaps lower for some of the higher elevation areas. A Cold Weather Advisory has been hoisted these areas. && .LONG TERM... Issued at 359 AM PST Sat Dec 27 2025 (Sunday through Friday) Ensemble guidance favors upper level ridging through Tuesday into Wednesday, with some uncertainty setting up for the end of the week. Models show that the upper trough gets elongated, cut off, and then shoved to the southwest over the Pacific. It then meanders there for quite some time while ridging nestles over us. By mid week guidance shows upper level troughing from the Gulf of Alaska trying to dig southwards pushing ridging to the east. It is here, where the models begin to show variance between upper level troughing and quasi zonal flow for the latter half of the work week. The NBM paints POP over us starting as early as early as late Wednesday into Thursday, with rain chances lingering through Friday. Rain at this point looks to be beneficial. It will be worth watching to see if the Gulf trough is able to breakdown the ridge and allow for the wetter weather pattern or if the ridge is a bit more resilient. Stay tuned to the forecast. && .AVIATION... (12Z TAFS) Issued at 341 AM PST Sat Dec 27 2025 Some very light, brief showers remain over the region this morning, but will be exiting the area by sunrise. Patchy MVFR stratus this morning associated with linger clouds from this week`s storm system and localized FG around KSTS will all clear to VFR by around sunrise today, then VFR persists through the rest of the TAF period. High confidence in mostly clear skies going into tonight and Sunday morning. Vicinity of SFO...Largely unproblematic forecast with skies clearing to VFR this morning and lasting through the TAF period (high confidence). One hitch may be a slight shift in the winds with a weak easterly component overnight tonight in the pre-dawn hours Sunday morning. So slight chance of NE/SE winds during this period, but speeds expected to remain below 6-7 kts. SFO Bridge Approach...Similar to SFO. Monterey Bay Terminals...Lingering showers this morning (light and brief), then clearing out to VFR by around sunrise. VFR through the rest of the period with generally light onshore winds during the afternoons (high confidence). && .MARINE... (Today through Thursday) Issued at 341 AM PST Sat Dec 27 2025 Very rough seas will begin to diminish this morning due to a combination of westerly swell and leftover southerly wind waves. Hazardous marine conditions will continue through the weekend with conditions improving by Monday. High pressure and dry weather return for the weekend and early next week. && .MTR WATCHES/WARNINGS/ADVISORIES... CA...Cold Weather Advisory from 2 AM to 9 AM PST Sunday for CAZ516>518-528. PZ...Small Craft Advisory until 9 AM PST this morning for Pigeon Pt to Pt Pinos 0-10 nm-Pt Arena to Pt Reyes 0-10 nm-Pt Pinos to Pt Piedras Blancas 0-10 nm-Pt Reyes to Pigeon Pt 0-10 nm. Small Craft Advisory until 3 AM PST Sunday for Pt Arena to Pt Reyes 10-60 NM. Small Craft Advisory until 3 PM PST this afternoon for Pigeon Pt to Pt Pinos 10-60 NM. && $$ SHORT TERM...KR LONG TERM....KR AVIATION...Behringer MARINE...Behringer 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

275 FXUS66 KOTX 271233 AFDOTX Area Forecast Discussion National Weather Service Spokane WA 433 AM PST Sat Dec 27 2025 .KEY MESSAGES... - Snow tapering off from north to south today with breezy to gusty north to northwest winds. - Much colder temperatures Saturday into Sunday. - Dry conditions through midweek then becoming unsettled late week into next weekend. && .SYNOPSIS... Drier and colder air works into the region from north to south today with snow showers waning. Blustery north to northwest winds will create biting wind chills. Seasonal temperatures and dry conditions settle into the region early next week followed by a more active winter weather pattern heading into 2026. && .DISCUSSION... ...Icy conditions Saturday morning... Saturday-Sunday: An influx of cold and dry continental air is ongoing this morning. Dewpoints through the Okanogan Valley and across the northern mountains have recently dropped in the teens to single digits. As of midnight, there were snow showers developing along cold front separating these air masses slowly sagging southward through the Northern Idaho Panhandle and northern mountains of NE WA. Winds have also shifted to the north and northwest with local gusts of 30-40 mph channeling through the Okanogan Valley. Well ahead of this front, gusty west to southwest winds are in place resulting in persistent orographic snow showers into the Palouse and Central Panhandle Mountains. We are also seeing gusts 30-40 mph from the foothills of the Blue Mountains, L-C Valley, and into the lower Idaho Panhandle. Over the next 6-8 hours, the front will continue to sag southward with clearing conditions across the north and continued snow showers from the Central Panhandle to the Camas Prairie and into portions of the Palouse and Blue Mountains. Snow showers will linger over the Camas Prairie and Blue Mountains through the afternoon while the remainder of the INW experiences afternoon sunshine. It will be an icy start to the weekend with nearly all sites below freezing and numerous reports of moisture already refreezing to surfaces however I don`t expect the ice to impact the roads very long following a few hours of sunshine. Temperatures will be much cooler than most of communities have experienced in the last 2 weeks with highs varying from the 20s across the northern mountains to 30s in the deep Basin. With breezy northwest winds, wind chills will make it feel even colder. Clear and dry conditions tonight will allow temperatures to plummet with readings falling into the teens to lower 20s. Would not rule out a few single digit readings sprinkled within the sheltered northern valleys where there is fresh snow. Strong morning inversions Sunday and light winds will be a good recipe to maintain cold afternoon highs to close out the weekend with readings remaining in the 20s-lower 30s. Models are hinting at a weak wave clipper system on Sunday. Given the dry dewpoints and low precipitable water readings, it will be tough to get much snow from this feature with passing clouds and perhaps a few flurries the most likely scenario. Monday-Wednesday: High confidence for a ridge of high pressure to setup over the region delivering stable weather conditons and dry conditions. Ensembles indicate a subtle warming trend but can often struggle with warming valleys to quickly under scenarios with strong nocturnal inversions and light boundary layer winds. 80% of the ensembles maintain the dry streak into Thursday with the other 20% beginning to flatten the ridge and introduce light precipitation over the Cascades and North Idaho. Roughly 70% of the ensembles shift the ridge axis eastward Friday into the weekend with a return of unsettled weather conditions with the arrival of a cool Pacific trough. Look for increasing chances for mountain snow during this time and wintry mix for the lowlands. Many many details to sort out for an event 6+ days out. Enjoy the dry conditions Inland NW! /sb && .AVIATION... 12Z TAFs: Last of the snow showers are moving into the central Idaho Panhandle as drier air filters into the Inland Northwest with a cold front. Residual moisture is resulting in MVFR ceilings at KCOE and KPUW. Expect intermittent MVFR conditions at KCOE through 16Z and more persistent MVFR conditions at KPUW through around 17Z. Elsewhere, the dry air has brought widespread VFR conditions. Breezy west winds will shift to the northwest this morning and remain breezy into the afternoon. The strongest winds will be felt across the Palouse and the L-C Valley (KPUW/KLWS) and through the Okanogan Valley (KOMK) with gusts 20 to 30 knots through the middle of the afternoon. Winds will decline around 22-23Z with most locations outside of the Okanogan Valley decreasing to below 10 knots Saturday evening. Once KCOE and KPUW improve to VFR, widespread VFR conditions are expected through much of the period. High resolution models are showing stratus developing across the Palouse, including KPUW, after 8Z and gradually creeping north into KGEG/KSFF/KCOE later Sunday morning or early afternoon. Highest confidence in MVFR ceilings in the next 24 hours exists at KPUW with a 40 percent chance at 8Z, increasing to a 50 percent chance by 12Z Sunday morning. .FORECAST CONFIDENCE AND/OR ALTERNATE SCENARIOS: High confidence for widespread VFR ceilings after 17Z with the influx of drier air. Moderate confidence in a return of MVFR conditions at KPUW near the end of the TAF period and low confidence at KGEG/KSFF/KCOE/KLWS as HREF probabilities for MVFR conditions do not increase to 20-30 percent until Sunday afternoon. ----------------------- 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 30 17 29 21 32 21 / 10 0 0 0 0 0 Coeur d`Alene 30 15 28 21 33 23 / 10 0 0 0 0 0 Pullman 30 18 30 21 33 24 / 30 0 10 0 0 0 Lewiston 38 24 33 25 36 28 / 40 0 0 0 0 0 Colville 23 14 24 17 29 20 / 0 0 0 0 10 0 Sandpoint 25 13 24 17 29 20 / 10 0 0 0 10 0 Kellogg 28 13 28 21 35 24 / 40 0 10 0 0 0 Moses Lake 34 20 32 22 35 23 / 0 0 0 0 0 0 Wenatchee 33 21 31 23 32 24 / 0 10 0 0 0 0 Omak 22 15 25 19 28 21 / 0 0 0 0 0 0 && .OTX WATCHES/WARNINGS/ADVISORIES... WA...Winter Weather Advisory until 10 AM PST this morning for Northeast Blue Mountains. ID...Winter Weather Advisory until 10 AM PST this morning for Central Panhandle Mountains-Lewis and Southern Nez Perce Counties. && $$

672 FXUS66 KPDT 271104 AFDPDT Area Forecast Discussion National Weather Service Pendleton OR 304 AM PST Sat Dec 27 2025 .KEY POINTS... 1. Mountain snow will continue through the early morning *Advisory in effect through 7 AM* 2. A high pressure ridge will dominate through mid-week 3. Likely return of precipitation late next week .DISCUSSION...Current radar shows some returns over the Cascades primarily focused along the WA. Cascades. Some lingering returns over the Northern Blues as well. Ground observations show light precipitation amounts have fallen over the last three hours of 0.01. Webcams do show wet roads along Snoqualmie Pass and the 84 corridor, but cannot distinguish and precipitation falling in the camera footage along the 90. However, cameras in the Tollgate and Spot Springs area show precipitation still falling. Models show that the mountain snow will continue through the early morning with raw ensembles showing a 40-60% probability of up to another 3 inches falling by 7 AM through the WA Cascades and the Northern BLues below 4500 ft. Winds will also remain a bit on the breezier side through the early hours as well with some areas seeing sustained winds between 10-15 mph with gusts of 25-30 mph. Once the remnants of the system move to the east, models show the leading edge of an upper level ridge moving into the region. Models show some lingering mountain showers will persist Saturday with the majority of the precipitation over the OR Cascades, eastern mountains and the Blues with 80-90% of the raw ensembles in agreement that snow accumulations of 1-1.5 inches of snow will accumulate Saturday. By Saturday night and into Sunday, models show the ridge to be pushing in with the axis just off the coast a models show it to continue to remain overhead through Thursday night. With the cold air that came into the region the last few days coupled with the incoming high pressure, pattern recognition of the area lets us know that the biggest weather concern while under the high pressure will be fog. Looking at raw ensemble visibilities, they already show the effects of the system with lower visibilities could plague the region as soon as Sunday (20-30% confidence). Dense fog and freezing fog will be the primary concern through mid-week (50-60% confidence). Thursday models show the ridge to begin to break down as an upper level begins to dig in from the northwest. Clusters show that there is a difference in the model solutions mainly with the timing and amount of precipitation this next event will bring. Regardless of those solutions, models are in agreement that there will be a change in the weather pattern as the weekend approaches. 90 && .AVIATION...12Z TAFs...VFR conditions ill prevail through the forecast period. The main concern will be with the winds as they continue to be breezy at most TAF sites. DLS/PDT/RDM/ALW/PSC are all seeing winds between 10-15 kts with PDT and DLS seeing gusts nearing 30 kts. Models show these winds to remain through 14-16Z or later. Winds in the aforementioned sites will remain near 10 kts even after 16Z. PSC will see a decrease to below 10 kts after 16Z while YKM is the only site seeing winds below 5kts and models show the site to remain calm through the period. 90 && .PRELIMINARY POINT TEMPS/POPS... PDT 40 25 38 23 / 30 10 0 0 ALW 38 26 37 25 / 50 10 0 0 PSC 43 22 37 22 / 0 0 0 0 YKM 40 21 36 21 / 0 10 0 0 HRI 43 24 38 23 / 10 0 0 0 ELN 35 19 32 21 / 0 10 0 0 RDM 39 19 39 20 / 0 10 0 0 LGD 33 23 35 22 / 60 0 0 0 GCD 34 22 38 22 / 30 0 0 0 DLS 45 30 40 28 / 10 10 0 0 && .PDT WATCHES/WARNINGS/ADVISORIES... OR...Winter Weather Advisory until 7 AM PST this morning for ORZ502- 509. WA...Winter Weather Advisory until 7 AM PST this morning for WAZ030- 522. && $$ SHORT TERM...90 LONG TERM....90 AVIATION...90

339 FXUS65 KREV 271012 AFDREV Area Forecast Discussion National Weather Service Reno NV 212 AM PST Sat Dec 27 2025 .KEY MESSAGES... * Dry but colder weather prevails this weekend with potential for freezing fog in the Sierra. * Quiet weather with morning inversions leading to air stagnation is expected next week over western NV valleys. * There is potential for the next storm system on New Years Day through the weekend, but the system looks weak compared to the last one. && .DISCUSSION... A few light rain and snow showers continue in the Sierra and NE CA as of 2 AM this morning per radar. This activity is expected to dwindle over the next few hours as the upper trough responsible for the weather over the last few days slowly leaves the region. A few stray showers could be possible today associated to that system, but any rain/snow accumulations will be minimal or nothing at all. Also freezing fog is likely, mainly over Sierra valleys this morning, once the skies clear out. In the wake of this system, we will have cold weather through the weekend as a northerly flow advects cold air towards northern NV/CA. Temperatures will be 5 to 10 degrees below average through early next week. Therefore, expect cold mornings and chilly afternoons. As the upper ridge moves slowly inland next week, temperatures rise to seasonal on Tue/Wed, above average by Thursday. So, we will get to enjoy some mild temperatures for the end of the year. Furthermore, the quiet weather will increase the chances for morning inversions leading to stagnant air early next week. The next system is forecast to arrive sometime around or after New Year`s Day. The models have diverging solutions with some showing a more progressive solution, while others are taking their time pushing this system into the Great Basin. The intensity of the system also vastly changes among ensemble and deterministic members of the GFS/ECMWF/CMC. However, the trend that can be seen is wetter and cooler conditions along with potential for gusty winds. It also appears that this system is looking weaker than the one that affected us this past Christmas. We will know more as we get better data over the next few days. -HC && .AVIATION... VFR conditions are expected across most of the area. However, there will be a few exceptions due to FZFG, which is very likely once the skies clear out resulting in IFR/LIFR conditions, especially for KTRK/KTVL. If FZFG develops at KTRK/KTVL it could last through 15-17Z this morning. Sfc winds will be generally light and VRB or from the north AOB 8 kts. -HC && .REV Watches/Warnings/Advisories... NV...None. CA...None. && $$

678 FXUS66 KSTO 261953 AFDSTO Area Forecast Discussion National Weather Service Sacramento CA 1153 AM PST Fri Dec 26 2025 For additional details on weather and expected impacts over the next 7 days, please visit weather.gov/sto/briefing. .KEY MESSAGES... - Major holiday travel impacts from periods of heavy rain, thunderstorms, heavy mountain snow, and gusty winds through today. - Heavy snow is expected through tonight, with snowfall rates of 1-2" per hour at times. - Periods of heavy rainfall are anticipated across the Valley and lower foothills with additional flood impacts possible. - Mountain showers linger Saturday, with drier weather expected Sunday into early next week. Fog/low clouds possible in the Valley/foothills once again. && .DISCUSSION... ...Today & Saturday... A period of clearing skies in the central Valley evident on satellite imagery this morning will provide another opportunity for isolated thunderstorm development this afternoon and early evening as the final few waves of atmospheric river moisture progress through interior NorCal. The most likely time frame for thunderstorms in the Valley and lower foothills will be between noon and 8 pm. Given a still moisture-rich environment with modest instability and synoptic scale support, gusty winds, small hail, heavy rain, and isolated tornadoes remain possible with any stronger thunderstorms that do develop. Flooding impacts remain possible as well for the Valley and lower foothills through the evening in periods of heavy rain. Across the mountains, snow levels are expected to remain steady around 4000 to 5000 feet through the afternoon and evening. Snow showers continue to provide brief bursts of moderate to heavy snowfall in the early afternoon, with heavy snowfall becoming more widespread as lower elevation convection moves up the terrain later in the afternoon and through the evening. Snowfall rates of 1 to 2 inches per hour will remain likely through the evening. As a result, an additional 8 to 12 inches will be possible above 4500 feet with up to 15 inches possible over peaks through Saturday morning. In addition to the precipitation impacts, breezy to gusty southerly winds are expected to continue this afternoon and evening as the weather system moves onshore. Strongest gusts up to 45 mph are expected across the northern Sacramento Valley. A brief lull in gusty winds is expected into the overnight hours as the system progresses eastward, with a period of breezier north winds gusting up to 20 mph at times to follow on Saturday. Otherwise, cool and mostly dry weather looks to settle in by Saturday for the Valley/foothills with light snow showers remaining possible along the Sierra throughout the day. Despite the system gradually beginning to wind down today, periods of gusty winds, heavy rain/mountain snow, and thunderstorm chances will result in difficult to dangerous travel conditions persisting through the evening and likely lingering at least into Saturday morning across the mountains. If you have travel plans plan ahead, make alternate routes, have backup plans, and carry safety kits with you in case of an emergency. If you see flooded areas, turn around don`t drown. ...Sunday Into Next Week... As the holiday week weather system finally wraps up across interior NorCal, ensemble guidance is uniformly indicating an amplifying ridge building into the region late weekend into early next week. This brief pattern shift will usher in a period of drier weather through the middle of next week. Despite this, the expected stagnating weather pattern will likely plunge Valley and foothills locations back into a similar cycle of fog and low clouds seen earlier this month. While the building ridge does look to amplify early in the week, latest ensemble guidance is depicting a closed low offshore of SoCal pushing northward as a Gulf of Alaska trough digs southward mid to late next week. Exact implications of this remain relatively uncertain, but this trend will likely result in the return of unsettled weather to the region by the new year at the very least. && .AVIATION... MVFR/VFR conditions are forecast to prevail through the afternoon and evening hours as a final wave of precipitation moves from northwest to southeast through the region. Could see some isolated thunderstorms embedded within this line, particularly for the Sacramento Area terminals. Any storms near a TAF location may reduce visibilities from heavy rain with brief IFR conditions, and would be accompanied by gusty/erratic winds. Snow levels are currently around 4500 feet in the Sierra and 3500-4500 feet in the Coastal Range/southern Cascades. && .STO WATCHES/WARNINGS/ADVISORIES... Winter Storm Warning until 10 PM PST this evening for Burney Basin / Eastern Shasta County-Mountains Southwestern Shasta County to Western Colusa County-Shasta Lake Area / Northern Shasta County-West Slope Northern Sierra Nevada-Western Plumas County/Lassen Park. Flood Watch until 4 PM PST this afternoon for Carquinez Strait and Delta-Central Sacramento Valley-Motherlode-Mountains Southwestern Shasta County to Western Colusa County-Northeast Foothills/Sacramento Valley-Northern Sacramento Valley-Northern San Joaquin Valley-Shasta Lake Area / Northern Shasta County- Southern Sacramento Valley. Wind Advisory until 6 PM PST this evening for Carquinez Strait and Delta-Central Sacramento Valley-Motherlode-Northeast Foothills/Sacramento Valley-Northern Sacramento Valley-Northern San Joaquin Valley-Southern Sacramento Valley. && $$

476 FXUS65 KMSO 270909 AFDMSO Area Forecast Discussion National Weather Service Missoula MT 209 AM MST Sat Dec 27 2025 .DISCUSSION... KEY MESSAGES: - Saturday Arctic Push: Flash freeze potential as bitterly cold air moves west of the Divide Saturday morning. Strong northeast winds will develop in prone canyons and gap areas (e.g., Bad Rock Canyon). - Building Ridge (Early Next Week): Cold and much drier conditions starting Sunday. A few lingering showers are possible today, potentially forming bands during the afternoon. Impacts will be isolated to these showers if they develop and should not be long lasting as they will propagate rapidly southeastward. An Arctic boundary is still on track to affect portions of northwest MT today. In fact, around 11:30 pm Friday the first hints of Arctic Air can be seen in weather stations just north of Cut Bank, MT where winds turned northerly. Its `pick your favorite weather model Friday` on timing of the front but a middle of the road timing would be: 6 am - 9 am Marias Pass 10 am - 2 pm Kalispell MT 1 pm - 5 pm Lincoln MT Sunday Morning low probability of reaching Missoula and Bitterroot Valleys There is decent confidence that US-2 from Marias Pass into the Flathead Valley will have Arctic Front impacts such as gap winds up to 40 mph, rapidly dropping temperatures, enhanced snowfall rates, and potential for wet roads to freeze up. Elsewhere, the only effects from the Arctic may be the coldest temperatures yet this season. For instance, the coldest temperature yet this season for Missoula has been 17F on Nov 30th. There is a 50/50 chance the low temperature will be below 10F on Sunday in Missoula. North and east of Missoula, expect lows of single digits above zero. Continued winds and cloud cover will likely inhibit temperatures from lowering below zero except in higher elevations. Now comes the difficult part of the forecast, a ridge will develop over the region on Sunday. Question is how does the ridge of high pressure play out? Valley locations that receive a few inches of snow by this evening, may quickly develop cold pools. These locations could see effects such as high temperatures remaining in the upper 20s for a few days, with low stratus or freezing fog for most of the mornings. In valleys that do not receive a few inches of snow, conditions will take longer to develop. Over a few days these locations will experience expanding areas of morning fog or low stratus, that lasts longer each day. High temperatures that quickly recover into the upper 30s Sunday, may slowly lower into lower 30s. It will be all about who gets a few inches of snow or not. High pressure is expected to last through the end of the coming work week. This looks to be a dirty ridge, so there will be times with moisture moving through the ridge producing clouds with low probability of any precipitation beyond a few light showers in the mountains north of I-90. && .AVIATION...An Arctic boundary is still forecast to impact KGPI between 27/1600 and 27/1900z. Expect winds to swing northeasterly with gusts 25 to 30 kts. A brief period of snow is possible with the front, temporarily lowering visibility and ceilings. Elsewhere, isolated showers are expected during the afternoon, they will also be capable of briefly lowering visibility and ceilings. && .MSO WATCHES/WARNINGS/ADVISORIES... MT...Winter Weather Advisory until 2 PM MST Saturday for Lower Clark Fork Region. Winter Weather Advisory until 8 PM MST Saturday for Bitterroot/Sapphire Mountains...Flathead/Mission Valleys... Potomac/Seeley Lake Region. Winter Weather Advisory until 5 PM MST Saturday for Kootenai/Cabinet Region...West Glacier Region. Winter Weather Advisory until 5 PM MST Saturday for Missoula/Bitterroot Valleys. Wind Advisory until 5 AM MST Saturday for Butte/Blackfoot Region. Winter Weather Advisory from 5 AM to 8 PM MST Saturday for Butte/Blackfoot Region. Wind Advisory until midnight MST tonight for Potomac/Seeley Lake Region. ID...Winter Weather Advisory until 1 PM PST Saturday for Northern Clearwater Mountains. Winter Weather Advisory until 8 PM MST /7 PM PST/ Saturday for Eastern Lemhi County...Southern Clearwater Mountains... Western Lemhi County. Winter Weather Advisory until 10 AM PST Saturday for Orofino/Grangeville Region. && $$

203 FXUS65 KBOI 271000 AFDBOI Area Forecast Discussion National Weather Service Boise ID 300 AM MST Sat Dec 27 2025 .SHORT TERM...Today through Monday night...A cold front is moving across southwest Idaho this morning, accompanied by isolated snow showers and gusty northwest winds. Snow levels will drop to valley floors behind the front. The mountains, particularly the West Central and Boise Mountains, will see additional light snowfall accumulations before precipitation tapers off from west to east this afternoon. A few snow showers are possible in the Snake River Plain, particularly this afternoon as convective showers develop, though no accumulation is expected. Gusty northwest winds will continue through the day with gusts to 40 mph, especially across open terrain, before diminishing this evening as the pressure gradient relaxes. The pattern shifts quickly tonight as an upper level ridge begins to build over the region. This transition will bring an end to precipitation and lead to clearing skies. However, the clearing skies and light winds will set the stage for strong radiational cooling and the development of valley inversions. Patchy fog and low stratus are expected to form in the sheltered valleys of southeast Oregon and southwest Idaho late tonight into Sunday morning. The central mountains will see some of the coldest temperatures so far this winter, with readings dropping below zero above 6500 feet. The ridge will strengthen Sunday and Monday, firmly establishing strong temperature inversions. This will lead to dry conditions but persistent low clouds and fog in the valleys, which will suppress daytime high temperatures. Conversely, mountain locations will experience mostly sunny skies and moderating temperatures. With limited mixing expected under the ridge, air stagnation could start to become a concern by Monday. .LONG TERM...Tuesday through Saturday...Pronounced upper ridging will characterize the start of the period, bringing dry conditions with temperatures near seasonal normals. This pattern will also promote inversion conditions in the valleys, resulting in higher probabilities of fog/low stratus each day and reduced air quality. Still a significant amount of uncertainty in exactly how the upper ridge breakdown process will unfold, with ECMWF AI members showing a more aggressive suppression of heights over the Northwest compared to other deterministic model solutions. However, model consensus is still relatively high that an anomalous area of moisture currently over the Southwest will advect northward into the region and bring higher chances of precipitation (generally 20-50%) from late Thursday through Saturday. Snow levels will generally remain below 5000 feet as well, resulting in periods of mountain snow. && .AVIATION...Scattered snow showers mainly over the higher terrain through this afternoon. IFR/LIFR in snow. Mountains obscured. Snow levels near valley floors. Surface winds: NW 5-15 kt increasing to NW-W 10-20 kt with 20-35 kt gusts late this AM. Winds aloft at 10kft MSL: NW 20-35 kt. KBOI...VFR. Showers in vicinity over Boise foothills, creating obscuration. Potential for brief snow shower and degraded visibility at KBOI Saturday mid morning through early afternoon. However, forecast confidence is very low as shower activity will be favoring higher terrain. Precipitation chances end after 22Z. Surface winds: W-NW 8-18 kt with gusts around 25 kt, decreasing this evening. Sunday Outlook....VFR, cold, and dry. Surface winds light and variable, except W-NW 10-15 kt with a few stronger gusts Sun AM in south-central Idaho (KTWF-KJER). && .AIR STAGNATION...Stagnant conditions develop Sunday as a ridge of high pressure begins to build over the area. Poor mixing heights with light winds expected Monday through Thursday. A temperature inversion will strengthen Monday through Wednesday of next week as the ridge moves overhead with warmer temperatures aloft. An advisory will likely be needed for next week. && .BOI WATCHES/WARNINGS/ADVISORIES... ID...Winter Weather Advisory until 5 AM MST early this morning IDZ011-013. OR...None. && $$ www.weather.gov/Boise Interact with us via social media: www.facebook.com/NWSBoise www.x.com/NWSBoise SHORT TERM...JDS LONG TERM....JR AVIATION.....JR AIR STAGNATION...JDS

078 FXUS65 KLKN 270848 AFDLKN Area Forecast Discussion National Weather Service Elko NV 1248 AM PST Sat Dec 27 2025 .KEY MESSAGES... Updated at 1235 AM PST Sat Dec 27 2025 * Breezy afternoon winds will develop again this afternoon across portions of northeast Nevada with wind gusts to 30 mph * Cooler temperatures this weekend through the start of next week, gradually rising to above normal levels by mid-week * Precipitation chances return to the area by the end of next week && .UPDATE... Issued at 1235 AM PST Sat Dec 27 2025 Given the recent precipitation across portions of northern and central Nevada, temperature/dewpoint spreads are closing within three degrees or less at various remote sites. Though cloud cover is expected over the eastern half of the forecast area, the western half has breaks in the clouds. Development of freezing fog is possible in the valley areas. As a result, have added this to the weather grids during the morning hours today across portions of northern Nye, western Lander/Eureka, and Humboldt counties. No other changes were made to the short term forecast. && .DISCUSSION... (This evening through next Thursday) WEATHER PATTERN OVERVIEW: A ULT pushing through the Great Basin continues to be the catalyst for active weather over the northern half of NV. An associated surface boundary pushing across eastern NV this afternoon is bringing rain and a brief changeover to wet snow to the area. Frontogenesis along and ahead of the boundary is helping to create brief but moderate snowfall for I-80 and eastern NV roadways where visibilities briefly drop to 3/4 mile as the band pushes through. An embedded south-southwesterly jet firmly entrenched over the area will continue to bring strong gusty winds to the area, especially over White Pine Counties through the evening where a Wind Advisory remains in place until tonight. Behind the front a post frontal regime will build into the area by Saturday evening as the upper level extent of the trough drags through the region. More northerly flow and eventually clearing skies will help drive temperatures back down to seasonal norms. Northerly flow in the eastern flank of a building ridge will continue to keep temperatures cooler into the new year. Unlike the previous ridge, the ridge that will build over Great Basin this weekend does not have a long residence time over the area. By midweek the ridge will migrate eastward placing the region in its westward flank and more southerly flow that will help warm temperatures back to above normal levels. Riding this southerly flow by Thursday and Friday of next week is a shortwave that will help return precipitation chances to the area for at least central and east-central NV. The wave will increase moisture availability, particularly over Nye and White Pine Counties by Wednesday evening. Current guidance has rain and snow shower activity pushing into the region from south to north by Thursday morning. It is a bit early to speculate on accumulations and amounts associated with this system. FORECAST CONFIDENCE & DEVIATIONS: High confidence remains in the short term forecast concerning precipitation timing and amounts through Saturday as well as cooler temperatures this weekend and early next week. Low confidence exists in precipitation chances for central and northeastern NV next Thursday and Friday. && .AVIATION... VFR conditions will gradually return to all terminals from west to east through Saturday afternoon. A cold front bringing -SHRASN activity will push through eastern NV and western UT by Friday evening bringing periods of MVFR and IFR conditions to KEKO, KELY, and KENV. Friday afternoon and evening southerly winds will be strong for KTPH and KELY gusting between 30-40KTs until later Friday evening. Gusts of around 22KTs are forecast at northern NV terminals until after sunset Friday evening. More westerly breezes are anticipated at KEKO, KELY, and KENV Saturday afternoon. && .LKN Watches/Warnings/Advisories... None. && $$ DISCUSSION...86 AVIATION...99