017 FXUS66 KSEW 212343 AFDSEW Area Forecast Discussion National Weather Service Seattle WA 343 PM PST Wed Jan 21 2026 .SYNOPSIS... A strong upper level ridge maintains dry conditions across western Washington through the rest of the week. A weak system will pass through on Thursday for increased cloud cover. High pressure rebuilds Friday and into the weekend, with little in the way of rainfall chances well into next week. && .SHORT TERM /TONIGHT THROUGH FRIDAY NIGHT/... More of the same across western Washington this morning as high pressure remains firmly in place. After a rather chilly start to the day with fairly widespread pockets of fog, skies are mostly clear across the region this afternoon save for a pocket of fog centered over the South Sound - specifically stretching from south of Brinnon southeast toward Eatonville. Temperatures largely in the 40s, except holding cold in the 30s for the areas that have remained in the fog. Increased mid-level clouds start to move over the area tonight with the ridge axis shifting a bit westward and opening the door for a weak impulse to slide through the region. This front offshore is containing to look less impressive and expect that the area remains dry, but the air mass will also cool a bit Thursday and Friday. Expect morning fog (lingering to be afternoon fog in the most stubborn spots to clear), and cooler but dry temperatures to remain the story into the weekend. Apparent temperatures are unlikely (less than 10% for most, less than 20% in the Tacoma to Olympia corridor) to dip enough to warrant a cold weather advisory. Nevertheless, temperatures will dip below freezing so any freezing fog that develops will have the potential to yield slippery conditions. && .LONG TERM /SATURDAY THROUGH WEDNESDAY/... Ensemble guidance remains in good agreement with high pressure initially holding for the start of the weekend. Ensemble guidance continues to support upper level ridging over the weekend, which would maintain dry conditions over western Washington. A weak system late Sunday into Monday which could produce light precipitation over much of area as the ridge slightly weakens and is undercut by an upper low. However, the majority of solutions would favor most areas still remaining dry throughout much if not all of next week. && .AVIATION...Very light surface flow with a northerly gradient is in place today, with skies clearing for most this afternoon. South Puget Sound is hanging onto some of the lower visbys, but should improve briefly before sinking back down after 06Z. VFR expected for the rest of the terminals this afternoon. Another round of fog is expected overnight, with the highest probabilities of low clouds below 3,000 ft AGL (35-40% in central Puget Sound and western Whatcom county) through 15Z. Given the cold overnight lows at or below freezing, some FZFG has been introduced to area TAFs for the early morning period. Fog will hang on later near PWT and OLM through around 20Z, clearing more significantly throughout the rest of Puget Sound by 18Z-19Z. There will be an increase in mid and upper level clouds as a passing disturbance moves over the area tomorrow. KSEA...VFR cigs are expected this afternoon and light flow less than 6kts likely throughout the rest of the TAF period. A deterioration back to MVFR early tomorrow morning has around a 40% chance of occurrence by 12Z. With temperatures at or below freezing overnight, the threat for freezing fog cannot be fully ruled out, and it may be introduced in the 00Z TAF package for planning purposes. A return to VFR cigs with an increase in mid to upper level clouds is expected tomorrow afternoon as a weak front dissipates over the area. 21 && .MARINE... Continued high pressure over the waters today with thermal low pressure situated near the coastline. This will maintain northerly winds across the interior waters and easterly winds along the Strait of Juan de Fuca and along the gaps in the coastal terrain, though speeds remain short of advisory thresholds. The only other impact of note will be the return of fog Thursday morning, especially over the interior waters, bringing visibility down to 1 NM or less late tonight through early Thursday. Flow turns northerly on Thursday as a weak frontal system approaches the coastline. High pressure will rebuild over the region later in the week while the thermal trough builds along the coast again. Another frontal system could reach the waters late in the weekend into early next week, allowing for winds to shift back to the south, but speeds still look to remain largely below advisory speeds. Meanwhile, seas hold at 4 to 6 ft this week over the coastal waters, before potentially building closer to 10 ft during the early to middle portions of next week. && .HYDROLOGY... No river flooding is expected during the next seven days. && .SEW WATCHES/WARNINGS/ADVISORIES... WA...None. PZ...None. && $$

666 FXUS66 KPQR 212148 AFDPQR Area Forecast Discussion National Weather Service Portland OR 148 PM PST Wed Jan 21 2026 .SYNOPSIS...Dry weather is expected to continue through most of the weekend as high pressure stubbornly holds overhead. Gusty winds persist through the Columbia Gorge. Expect cold overnight lows in the in the low 30s to mid 20s tonight and likely tomorrow night. Clear skies, and light winds away from the Columbia River Gorge will result in frost and/or freezing fog formation for a decent swath of the interior lowland valleys and coast range Valleys. Near/below freezing temperatures in combination with any fog/frost may lead to locally slick road conditions. Chances for precipitation return towards the end of the week as well as by the middle of next week, but details on the exact timing and impacts remain rather uncertain at this time. && .DISCUSSION...Now through Tuesday...Dry weather is here to stay through much of the weekend and into the start of next week as ensemble guidance (GFS, Euro, and Canadian) are in good agreement that the ridge of high pressure will remain anchored over the Eastern Pacific/Pac NW. However, ensembles indicate that an incoming, shortwave trough will result in heights slowly lowering over the PacNW through the latter part of the week. This will allow a break down of the strong pressure gradients over the Cascades for the latter part of this week. Gusty offshore/east winds persist through the western Columbia River Gorge and into the eastern Portland metro with peak gusts up to 40 mph through the eastern Portland metro, including Troutdale, and up to 65 mph for windy locations east of Troutdale. As the pressure gradient slowly weakens over the next 48-72 hours, the extent and strength of gusty offshore winds through the Gorge will follow suit. However, wind prone areas near the Gorge will continue to see breezy winds into the weekend. Even with a weak shortwave moving in from the north, expect mostly sunny skies for the region through the end of the week. Under mostly clear skies, overnight temperatures will continue to be on the cold side with morning low temperatures near to below freezing across most of the region, for those areas outside of the influence of offshore winds through the Gorge. Clearing skies tonight will result in overnight lows as well as apparent temperatures (often called wind chill or "feels like" temperatures) dropping into the low 30s to mid 20s for lowland areas. For higher elevations, the temperature inversion that has been keeping higher elevations 5 to 10 degrees warmer will persist. So, have issued a Cold Weather Advisory for the majority of lowland areas within the Willamette Valley to include: North and Central Coast Range Valleys of Oregon, Lower Columbia River and Cowlitz River Valleys, Clackamas County Cascade Foothills, North Clark County Lowlands, Inner Vancouver Metro, Central and Southern Willamette Valley, Tualatin Valley, North and Central Coast Range Mountains of Oregon, Portland Metro Hills, and South Washington Cascade Foothills. These areas are expected to experience at least 4 hours or more of apparent temperatures at or below 25 degrees. Given the minimal changes expected for Friday night/Saturday morning, there is a moderate to high probability (45-70%) for another Cold Weather Advisory to be issued. These cold, overnight conditions are also expected to persist through Saturday night/Sunday morning. With the cold temperatures, freezing fog or frost concerns continue in the southern Willamette Valley, northern Cowlitz county valleys, and the Upper Hood River Valley each overnight through morning hours into the weekend. Any freezing fog or frost that develops could lead to locally slick road or sidewalk conditions. Additionally, stagnant air will be a continued concern under the subsidence inversion, leading to air quality concerns into Friday. Mixing heights will remain low and transport winds will be weak through the week. Therefore, an Air Stagnation Advisory is in effect through Friday after which point there`s moderate confidence in improvement. The Portland Metro area from the West Hills eastward were not included in this advisory due to stronger winds from the Gorge maintaining a more mixed atmosphere. Looking at early next week, ensemble guidance continues to push back the return of precipitation to NW Oregon and SW Washington. Currently, ensemble members are in good agreement that a weak low pressure system will move through the NE Pacific Thursday/Friday and will help to provide a momentary break from the current conditions. However, guidance continues to weaken this low as it approaches the region resulting in PoPs of 15-30% along the OR and WA coasts. There is good ensemble agreement that ridging returns by Friday and Saturday and will bring much colder, overnight temperatures across the CWA along with a return of onshore flow. As we move into the start of next week/middle of next week, ensembles are now showing a signal for a more significant pattern change. Models are showing a broad area of low pressure, sliding into the region from the NE Pacific and that could bring relatively warm and moist air into the Pac NW. Still, it should be noted, that model runs keep pushing the pattern change further and further into the future. Nevertheless, we will continue to diligently monitor and update the forecast as needed. /42/03 && .AVIATION...Dry northwesterly flow will continue aloft today as high pressure remains over the region. An upper low off the California coast will maintain scattered high clouds over northwest Oregon today. Otherwise, expect predominately VFR conditions to persist through this evening across the area. Chances for IFR to LIFR fog/stratus returning to the southern Willamette Valley increase to 30-40% at KEUG by 10z Thursday. The offshore pressure gradient in the lower levels continues to support easterly winds through the Portland area. East winds with gusts to around 30 kt will continue at KTTD through this evening. KPDX AND APPROACHES...VFR with scattered high clouds decreasing through the day. Southeast winds around 10-14 kt expected through this evening. East winds remain breezy for east approaches with gusts to around 30 kt at KTTD. /DH && .MARINE...Rather benign conditions continue across the coastal waters. High pressure builds slightly offshore and persists over the waters through the end of the week, while the high pressure inland weakens somewhat. This will allow for the offshore winds to diminish as the northerly winds become more dominant by Thursday. Offshore winds return Friday as the thermal trough along the coast expands northward, and higher pressure rebuilds inland through the weekend. Generally, winds are expected to remain 15 kt or less. Seas are expected to persist at around 4 to 6 ft with wave periods varying between 11-15 seconds through the weekend. Not much change to the overall sea state into early next week. /DH && .PQR WATCHES/WARNINGS/ADVISORIES... OR...Air Stagnation Advisory until noon PST Friday for ORZ104-105-108- 109-114>118-123. Cold Weather Advisory from midnight tonight to 10 AM PST Thursday for ORZ104>110-113>118-123. WA...Air Stagnation Advisory until noon PST Friday for WAZ204>206. Cold Weather Advisory from midnight tonight to 10 AM PST Thursday for WAZ204>206-208. PZ...None. && $$ www.weather.gov/portland Interact with us via social media: www.facebook.com/NWSPortland x.com/NWSPortland

359 FXUS66 KMFR 212350 AFDMFR Area Forecast Discussion National Weather Service Medford OR 350 PM PST Wed Jan 21 2026 .DISCUSSION...Updated aviation discussion. && .AVIATION...22/00Z TAFs...Dry weather will persist tonight through Thursday. IFR/LIFR fog/low clouds will continue in portions of the Umpqua Basin, including Roseburg. After breaking to VFR for the first time in over a week this afternoon, areas of LIFR are expected to redevelop in/around Grants Pass. Patchy IFR fog could also develop around Medford toward sunrise, but it should be short-lived. The remainder of the area will be VFR with varying amounts of high cirrus. && .PREV DISCUSSION... /Issued 213 PM PST Wed Jan 21 2026/ DISCUSSION...Satellite imagery this afternoon shows persistent fog in the Umpqua Basin and Illinois Valley/Grants Pass area, along with some higher level clouds streaming overhead. Also seen on satellite is a weak low pressure moving towards the California Coast. Aside from some increased cloud cover, we don`t expect much change in the overall day to day conditions through the remainder of the week. Fog and freezing fog will remain or return to the same places as the day before, and we`ve gone ahead with another freezing fog and dense fog advisories for tonight into Thursday morning. Additionally, while mixing will improve slightly today, we decided to extend the Air Stagnation Advisory through Friday afternoon. Conditions aren`t really improving on a large enough scale until a shortwave moves into the region Friday afternoon. Details can be found at NPWMFR. Low pressure currently seen on satellite is interrupting the overall ridge pattern we`ve been in for several days now. The ridge will rebound over the eastern Pacific late Thursday into Friday, albeit weaker and farther west than recent days. This will allow some inside slider shortwaves to dive down the back side Thursday night into Friday and again Friday night into Saturday. Overall, there won`t be much change in the sensible weather with these shortwaves, but expect some increased cloud cover Thursday night into Friday evening. Status quo is expected for the remainder of the week. Late Friday into Saturday and through the weekend, we`ll remain on the back side of the ridge under northerly to somewhat northwesterly flow aloft. Following the shortwave expected Friday night into Saturday, surface high pressure strengthens over the East Side and this will bring a round of dry easterly flow to the region for Saturday morning through Sunday. The air mass will dry significantly under this downslope flow, which could bring some fairly cold temperatures both Saturday and Sunday mornings. Much will depend on if this dry air can mix down into the valleys to keep fog from forming, but current forecasts keep fog out of the area over the weekend, which would allow for increased radiational cooling and lowering temperatures compared to recent nights. In fact, we may need to consider some Cold Weather Advisories for areas west of the Cascades where low temperatures are forecast to reach within a few degrees of advisory criteria (15 degrees for northern California/20 degrees for Jackson/Josephine Counties/25 degrees Douglas County). While the East Side will see some cold temperatures as well (teens to single digits), forecasted values don`t come as close to advisory criteria (0 degrees) for this time. Additionally, with this dry air mass settling over the region, expect continued moderate to poor recoveries and unseasonably low day time humidities across the region through the weekend. Beyond the weekend, the pattern looks to be more progressive for the first half of the week compared to recent weeks. By early next week, additional shortwaves pass through the region in a more west to northwesterly flow, which will continue to weaken the ridge pattern. Widespread precipitation is still not expected, however, we`ll see moderating conditions with improved/higher humidities/recoveries and overnight temperatures more typical for this time of year. Ensembles continue to show the potential return to active weather towards the latter half of next week (January 28th-30th) into early February. AVIATION...21/18Z TAFs...LIFR ceilings and visibilities persist this afternoon within Roseburg(KRBG) and Grants Pass(K3S8). It`s pretty much rinse and repeat from yesterday with some high clouds in the area as a relatively dry upper level low lingers off the coast of California this afternoon. We`ll see yet another round of fog and lower ceilings later tonight as high pressure still has some grip on the area. Medford(KMFR) could see some fog around Thursday morning at sunrise as it has happened the last few mornings. -Smith MARINE...Updated 300 PM PST Wednesday, January 21, 2026...Below advisory seas remain in the forecast for area waters through this afternoon. A west swell composed of two smaller swell groups will persist in the forecast area through the weekend. Northerly winds will begin to increase Thursday morning and continue to strengthen by Friday. Seas will increase and become steep and hazardous to smaller crafts south of Cape Blanco, especially beyond 10 nm from shore. Sustained winds will be 20 to 25 knots with gusts to 35 knots with seas under 10 feet. Winds will weaken by Saturday as easterly flow develops and high pressure builds farther inland. A more active pattern is expected next week and there is a moderate(50%) chance at an actual front moving through the waters around the Wednesday and Thursday time frame. -Smith && .MFR WATCHES/WARNINGS/ADVISORIES... OR...Air Stagnation Advisory until 4 PM PST Friday for ORZ023-024-026- 029>031. Dense Fog Advisory from 7 PM this evening to noon PST Thursday for ORZ023. Freezing Fog Advisory from 7 PM this evening to noon PST Thursday for ORZ024. CA...None. PACIFIC COASTAL WATERS...Small Craft Advisory from 4 AM Thursday to 4 PM PST Friday for PZZ356-376. && $$

234 FXUS66 KEKA 212252 AFDEKA AREA FORECAST DISCUSSION National Weather Service Eureka CA 252 PM PST Wed Jan 21 2026 .SYNOPSIS...Dry weather and above normal daytime temperatures will continue through the early next week. Overnight and morning temperatures will remain chilly with patchy dense fog along the river valleys and around Humboldt Bay. Chance of precipitation increase by mid next week. && .DISCUSSION...Partly to mostly cloudy skies are observed across NW California this afternoon, with mid- to high-level clouds streaming northward. This moisture is associated with a cut-off low approximately 330 miles off the Central California, which continues to track southward. High pressure will rebuild in the wake of this low tonight through Friday, leading to drier offshore flow. This will promote improved sky conditions on Thursday, with clear skies across much NW California Friday and into the weekend. A dry offshore flow will most likely reinforce chilly overnight lows, bringing a chance of near-freezing or freezing temperatures to coastal areas and adjacent valleys Friday night into Saturday morning. Granted places where winds stay up all night, temperatures probably will not even fall below 50F. Lower dewpoints, clear skies and light winds at night will allow for ideal long wave cooling again. Freezing or near-freezing temperatures are probable Friday and Saturday morning, both along the coast and in the wind- sheltered coastal valleys. Sub-freezing temperatures are a sure thing in interior valleys, especially Trinity and northern Mendocino. Dry weather is expected to persist through the weekend and into early next week as the high pressure persist over the Eastern Pacific, though the ridge weaken. A weak shortwave trough will bring increasing cloudiness Saturday night and Sunday. Coastal stratus are anticipated to redevelop, with a slightly deeper marine layer along the North Coast. Aside of some patchy coastal drizzle, generally dry conditions and above normal daytime temperatures are expected to continue through the early next week. Long-range models continue to suggest an increasing chance of precipitation from mid- to late next week. Uncertainties remain high in the details. Stay tuned for updates as the timing of this shift become clearer. /ZVS && .AVIATION...(18Z TAFs)...Upper low over the offshore waters of Central California will continue to spread occasional mid and high level clouds over the areas tonight. Offshore low has induced a slight N-NE flow over coastal areas and stratus and fog has been much less persistent for the Humboldt Bay area and over KACV vs the last 2 days. High resolution mesoscale ensemble (HREF) indicate lower chances for LIFR tonight for coastal forecast terminals. High boundary layer humidity may still result in mostly MVFR vsby obscuration in mist once the sun goes down and perhaps fleeting ceilings around 500-1500 feet. Otherwise, expecting mostly VFR conditions except for patches of fog and low clouds in the interior river valleys late tonight and early Thu morning. Northerlies increase offshore late on Thu, however shallow low level turbulence and/or low level wind shear will most likely not become a hazard for small aircraft until Thu night after 23/00Z. && .MARINE...Northerly winds will increase slightly tonight as a weak low approaches the central and southern California coast while high pressure noses toward the Pac NW coast. Surface wind fields do not appear strong enough to warrant an advisory for small craft tonight with gusts up to 18-22 kt and short period waves 5 ft or less for the outer waters. Northerly pressure gradients tighten on Thu as a mid level shortwave trough in NW flow aloft moves across the Pac NW. High resolution ensemble guidance indicates high chances for gusts to 25-30 kt (80% chance or more) with gale gusts over 34 kt much more probable (>60% chance) for the northern portion of pzz470 by 4 to 8 PM Thursday. Gale gust coverage increases after 8-10PM with very steep seas building to 9-11 ft overnight into Friday. Thus the watch for gales has been upgraded to warning as combined seas build to 12 to 15 feet in the outer waters by Fri afternoon. Ocean conditions will also deteriorate Thu night and Friday for the inner waters. Gale gusts are certainly probable around notorious wind prone locations such as Cape Mendocino and perhaps around Pt St George. Primary hazard for the waters appears to be large steep waves arising from the strong northerlies offshore. Confidence seas will be sufficiently elevated and very steep for a warning across the inner waters is not high. Perhaps buoys on the outer fringes of the inner waters will be report warning criteria. For now, a small craft advisory will be sufficient to let mariners in small craft know about deteriorating marine conditions and plan accordingly. Now conditions look to gradually improve over the weekend as the axis of strong north wind shifts outside of NW California waters and steep wind waves gradually subside. In this mix of steep short period waves will be a long period (>16 seconds) westerly swell on Thu that will decay through Fri. A mid period swell near 14 second follow on Fri, followed by third mid period group on Sat. None of these appear to pose a risk for sneaker waves at this time. && .EKA WATCHES/WARNINGS/ADVISORIES... CA... None. NORTHWEST CALIFORNIA COASTAL WATERS... Small Craft Advisory from 7 PM Thursday to 3 AM PST Saturday for PZZ450. Small Craft Advisory from 10 PM Thursday to 3 AM PST Saturday for PZZ455. Small Craft Advisory from 10 AM to 10 PM PST Thursday for PZZ470-475. Gale Warning from 10 PM Thursday to 3 AM PST Saturday for PZZ470-475. && $$ NOTE: The full forecast discussion is now regularly issued between 10 am/pm and 1 pm/am. Additional updates will be issued as needed. Visit us at https://www.weather.gov/eureka Follow us on Facebook and Twitter at: https://www.facebook.com/NWSEureka https://www.twitter.com/NWSEureka For forecast zone information see the forecast zone map online: https://www.weather.gov/images/eka/zonemap.png

430 FXUS66 KMTR 220351 AFDMTR Area Forecast Discussion National Weather Service San Francisco CA 751 PM PST Wed Jan 21 2026 ...New UPDATE... .KEY MESSAGES... Updated at 116 PM PST Wed Jan 21 2026 - Morning fog across North Bay and East Bay Valleys - Sprinkles or very light rain tonight into Thursday morning across the Central Coast and portions of the Bay Area - Increased offshore wind potential across higher terrain of the North Bay late Friday into Saturday && .UPDATE... Issued at 745 PM PST Wed Jan 21 2026 The 00Z weather balloon found dry air in the low levels beneath a quite deep moist layer. The current cloud deck extends from roughly 13,000 ft to 33,000 ft. The radar is showing some good returns over the water, but the upper level low is basically just spinning in place after being abandoned by the jet stream. There is still a slight chance for some of this light rain to reach the coast and push inland through the night, but it will be battling the dry air below 700 mb. && .SHORT TERM... Issued at 116 PM PST Wed Jan 21 2026 (This afternoon through Thursday) Generally quiet with largely mild conditions this afternoon across the Bay Area and Central Coast. Fog continues to slowly erode at this hour, with predominantly mid/upper level clouds continuing to overspread the area. Our upper low continues churn and WV/RAP mesoanalysis trends indicates that it continues to make it slow trek to the south and east. This is in line with current thinking. Radar imagery this afternoon has shown a couple of brief attempts at a loosely organized bands of what is largely virga/fall streaks. While the trends haven`t been encouraging, satellite imagery indicates still some mid-level cumuliform clouds/instability that may swing to the NE and give us another shot as sprinkles or very light rain after 4pm this evening and continuing through the pre-dawn hours on Thursday and this seems in alignment with latest short term guidance. As noted this morning, PoPs of 20-40% are advertised which remains along the higher end of the near/short term hi-resolution model guidance. Rain amounts at this time are anticipated to average around a few hundredths of an inch with the higher end scenario (10% chance of occuring) advertising a larger QPF footprint (light rain as far as the North Bay) and up to a tenth of an inch across the higher terrain of Central Coast. As the main upper low continues to pivot eastward, subtle 700mb WAA may lift northward through the Central Valley and into the North Bay. While some orographic ascent cannot be ruled out along the eastern slopes of higher terrain, the dry low levels should translate to a low probability for measurable precipitation here, even though radar may look rather ominous. Otherwise, fog, albeit limited due to the cloud cover, may continue overnight and into early Thursday morning. However, additional low level mixing thanks to the elevated wind field make keep the footprint smaller than previous nights. && .LONG TERM... Issued at 116 PM PST Wed Jan 21 2026 (Thursday night through next Tuesday) Thursday evening will feature a subtle PV anomaly will ripple through the Great Basin and help sweep the initial upper low eastward. In its` wake, mid/upper level ridging is forecast. This will promote surface pressure rises across the Great Basin and tighten local MSLP gradients across the region. More importantly, the 925mb flow will increase with even coarser guidance advertising 30-40 knots out of the north through the Sacramento Valley. The synoptic scale background/pattern recognition in tandem with the Extreme Forecast Index (EFI) would suggest an opportunity to alter messaging to advertise a noticeable uptick in winds, largely across the higher terrain of the North Bay and East Bay Hills. 2km PG&E WRF cross sections also indicate the potential for mountain wave type activity near and downwind of Mt. Saint Helena which could help enhance wind gusts. Given the highly localized nature of these phenomenon, have opted for targeted edits across the Mayacamas and higher terrain of the East Bay such that wind gusts reflect a blend of some of the higher end NBM percentiles. While fuel moistures have dried some, ERC values remain safely below critical fire weather thresholds. That said, please always be mindful that winter fuels could still promote some fire growth/smoke production. Overall, the themes in the extended forecast have not changed much. Ridging is anticipated to resume this weekend and largely dominate the weather pattern across the region through the early to middle part of next week. Thereafter, about one-quarter of the multi-model ensemble advertises more vigorous troughing across the Pacific NW. This would dampen out the ridge such that mid/upper level flow becomes more southwesterly, potentially opening the door for a disturbance or two. While the official forecast paints broad PoPs across most areas (minus the far interior Central Coast), there still remains some model variability with some NWP "clusters" indicating little to no chance for precipitation. We`ll continue to delve deeper into the model guidance with time. && .AVIATION... (00Z TAFS) Issued at 334 PM PST Wed Jan 21 2026 Expect VFR conditions for the remainder of the afternoon and evening for all terminals. Later tonight through early Thursday morning there is chance for MVFR/IFR ceilings to develop, however confidence is low in the exact timing and extent. Low stratus is possible for terminals closer to the coast with weak onshore flow at times. Fog is expected to develop in the North Bay, however hi- res guidance has a weaker signal than previous few days. Vicinity of SFO...Weak onshore flow may result in low stratus developing overnight into early Thursday morning, however the winds will be light and occasionally offshore, thus chances seem too low for dropping cigs into MVFR for the TAF. SFO Bridge Approach...Similar to SFO. Monterey Bay Terminals...Expect VFR for the remainder of the afternoon and evening. Weak onshore flow is expected to become offshore once again later tonight as an offshore upper level disturbance passes to the south. There is a chance for some brief periods of light rain as well when MVFR cigs may develop. Steadier but still weak onshore flow returns late in the TAF period. && .MARINE... (Tonight through next Monday) Issued at 334 PM PST Wed Jan 21 2026 Gentle to moderate northerly breezes and moderate seas persist through Thursday morning. On Thursday afternoon into Friday, winds will increase to a fresh northerly breeze along with building rough seas. Strong to near gale force gusts will create hazards for small craft across the northern outer waters, with gale force gusts possible in the far northern outer waters. Conditions will improve over the weekend as a light to gentle breeze settles in and seas gradually subside to slight Sunday through Monday. && .MTR WATCHES/WARNINGS/ADVISORIES... CA...None. PZ...Small Craft Advisory from 3 PM Thursday to 9 PM PST Friday for Pt Arena to Pt Reyes 10-60 NM. && $$ SHORT TERM...Bain LONG TERM....Bain AVIATION...JM MARINE...DialH 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

577 FXUS66 KOTX 212322 AFDOTX Area Forecast Discussion National Weather Service Spokane WA 322 PM PST Wed Jan 21 2026 .KEY MESSAGES... - Low confidence in a break of the quiet weather pattern by the end of the weekend into early next week. && .SYNOPSIS... Strong high pressure will dominate the weather this week, with quiet weather expected for the Inland Northwest. Dry conditions will persist until at least Sunday, with the potential for a return of light precipitation over the mountains on Monday. && .DISCUSSION... Wednesday through Sunday: A strong upper-level ridge remains offshore the Pacific Northwest, with the Inland Northwest under the influence of a dry, stable pattern. Strong low-level inversions and light winds have kept the Inland Northwest under a blanket of stratus, with this trend continuing through the evening and tomorrow. Some subtle changes are expected Thursday evening as a weak shortwave slides into the PNW from the north. This is not expected to bring precipitation to the Inland Northwest with drier continental air filtering into the region. Models show precipitable water values dropping from 0.25-0.35 inches Thursday afternoon to 0.10-0.15 inches by Friday morning. A increase in the northerly pressure gradient combined with temperatures cooling aloft will allow for better boundary layer mixing with a 70% chance for sustained winds greater than 12 mph across the Okanogan Valley, Columbia Basin, and into the Spokane area on Friday. While that does not seem overly impactful on its own, these winds would be strong enough clear out the persistent stratus the Inland Northwest has been experiencing aka sunshine! The clearing would also allow overnight lows to drop into the teens to low 20s across the region with upper single digits to low teens across the northern valleys. Monday through Wednesday: By the end of the weekend into early next week, models show the offshore ridge to gradually weaken with an upper-level trough approaching the Pacific Northwest. This trough is not expected to be very strong with limited moisture. This brings a 15-25% chance for very light snow across the mountains on Monday with the lowlands remaining dry. Tuesday into Wednesday, ensemble means depict the offshore ridge shifting east over the Pacific Northwest as a deeper system moves across the northern Pacific. There is some uncertainty in the strength of this ridge with a majority of ensembles suggesting a stronger ridge, keeping conditions dry into the middle of the week. However, a secondary scenario suggests a weaker ridge which would allow storm systems to penetrate inland and support precipitation mid- week. Currently the forecast for Wednesday has a 15-20% chance for precipitation across the lowlands and a 25-40% chance for the mountains. /vmt && .AVIATION... 00Z TAFs: Widespread MVFR stratus deck with calm or light winds to continue through 00Z THU. Models continue to struggle with the cloud deck so persistence has the best chance for verification. FORECAST CONFIDENCE AND/OR ALTERNATE SCENARIOS: High confidence in widespread MVFR conditions with the low stratus cover. ----------------------- 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 27 30 19 29 16 29 / 0 0 0 0 0 0 Coeur d`Alene 27 31 18 30 14 30 / 0 0 0 0 0 0 Pullman 25 32 22 31 18 31 / 0 0 0 0 0 0 Lewiston 30 35 25 34 21 34 / 0 0 0 0 0 0 Colville 28 32 16 30 13 30 / 0 0 0 0 0 0 Sandpoint 27 32 18 27 15 27 / 0 0 0 0 0 0 Kellogg 25 31 17 27 13 29 / 0 0 0 0 0 0 Moses Lake 29 33 22 36 18 32 / 0 0 0 0 0 0 Wenatchee 29 33 24 34 21 33 / 0 0 0 0 0 0 Omak 26 32 22 34 18 31 / 0 0 0 0 0 0 && .OTX WATCHES/WARNINGS/ADVISORIES... WA...None. ID...None. && $$

690 FXUS66 KPDT 212221 AFDPDT Area Forecast Discussion National Weather Service Pendleton OR 221 PM PST Wed Jan 21 2026 .KEY POINTS... 1. A high pressure ridge will dominate and dry northwest flow will persist through the short term period 2. Fog and stratus will be the main concern through the period .DISCUSSION...Current satellite shows a very predominant stratus deck in place over the CWA with only the eastern mountains seeing a slight reprieve from the clouds. This has aided in keeping temperatures cool. Highs today across much of the region, with the exception of central OR south and southeast of Bend, will be below 35 degrees while the aforementioned areas will be in the low to mid 40s. Models are in form agreement that there upper level high pressure system will remain overhead through Friday ahead of a weak shortwave. That shortwave is expected to move over the region Thursday night into Friday. However, guidance shows this to be mostly dry with no expected precipitation (80+% confidence). Also, 700-500 mb guidance shows very little instability and the omega field shows little to no mixing. With that, fog and low stratus will likely continue even with the disturbance coming through Friday. After Friday, models remain in relatively good agreement that another high pressure ridge and dry northwest flow will set up over the region. This will continue to keep the stratus decks low and allow for fog to reform. Especially in the valley areas with pattern recognition allowing confidence in the forecasted decks and fog to be relatively high (60-80% confidence). With this, temperatures will remain cooler under the stratus deck with temperatures averaging in the mid to upper 30s with a few locations seeing low 40s by the end of the weekend. By the beginning of the week, models diverge a bit with the ECMWF keeping the ridge over head but weakening, while the GFS breaks down the ridge and shifts the flow to the west. Guidance shows winds to remain calm through the transitions as well. With that said, confidence in how next week will shake out is low/moderate (40-60% confidence) in which way the models swing. If we keep the ridge overhead, fog and stratus will remain the concern. If we turn westerly, warmer temperatures could be in store if the system can scour out the cold pool. 90 && .AVIATION...00Z TAFS...Not much change expected across the area with continued low clouds and areas of fog. Generally MVFR conditions currently, with IFR/LIFR in a few areas. Some decrease in CIGS/VSBYS is possible overnight. WInds are expected to be light. && .PRELIMINARY POINT TEMPS/POPS... PDT 24 32 21 33 / 0 0 0 0 ALW 27 29 23 33 / 0 0 0 0 PSC 26 33 23 39 / 0 0 0 0 YKM 23 34 21 37 / 0 0 0 0 HRI 26 36 23 37 / 0 0 0 0 ELN 22 32 20 33 / 0 0 0 0 RDM 18 29 17 32 / 0 0 0 0 LGD 21 33 20 35 / 0 0 0 0 GCD 21 32 22 37 / 0 0 0 0 DLS 29 38 26 39 / 0 0 0 0 && .PDT WATCHES/WARNINGS/ADVISORIES... OR...Freezing Fog Advisory until 10 AM PST Thursday for ORZ050. WA...None. && $$ SHORT TERM...90 LONG TERM....90 AVIATION...77

603 FXUS65 KREV 212002 AFDREV Area Forecast Discussion National Weather Service Reno NV 1202 PM PST Wed Jan 21 2026 .KEY MESSAGES... * Light winds, valley inversions, and dry conditions will continue through midday Thursday for all valleys with freezing fog for Sierra Valleys and Mono Lake. * Ridge winds will increase Thursday into Saturday along with low chances for showers in the Sierra and portions of western Nevada. * Saturday will be the coldest and windiest day of the week with hazardous wind chills for backcountry areas. && .DISCUSSION... The grey, gloomy skies will persist through the end of the week until a dry cold front clears the skies over the weekend. Although, our brief break from the sun doesn`t even compare to the persistent freezing fog that has plagued the Mono Lake region for much of the month with little reprieve. Here`s what will bring some changes to the weather over the weekend and into early next week. A cutoff low along the CA coast is the reason we`re all clouded over today, but this storm won`t bring much meaningful weather to us other than the cloud cover. It`s forecast to drop southward through the weekend, leaving us with very low chances for showers tonight into Thursday across the high Sierra in Mono County. While we will see an uptick in breezes along the ridge tonight, the more "productive" winds will arrive Friday into Saturday. A dry, fast- moving trough drops through the Great Basin Friday into Saturday bringing northeast/east winds (gusts 20-30 mph) that should help to scour out the stagnant pockets of inversions in most areas, and hopefully for our friends in Mono county too! There are some low showers chances that accompany this northerly push of cold air through the region, but the majority of the shower potential will remain for areas south of Highway 50. For context, there is a 10-15% chance of 0.01" in Hawthorne and a 20-30% chance of that near Mammoth and June Lakes. There could be localized slick conditions, so just be aware that it won`t be as bone dry as of late! Saturday will feel quite brisk and chilly overall with the breezes and the colder air (about 10 degrees colder!). With wind gusts 50-60 mph for the high terrain, wind chills will dip into the single digits. Prepare accordingly if you have backcountry and/or resort recreation plans. It will be a far cry from the milder temperatures we saw over the holiday weekend. After Saturday we will see a gradual warming and drying trend as we start the next week. While there are some mixed signals for the extended forecast, it does look there is a hint of hope for a more progressive pattern. The GFS/EC ensembles for IVT do show higher probabilities (50-70%) of IVT landfall along the Pacific Northwest coast for the end of the month and into early February. Signals do appear to drift a bit further south, into the Sierra area by early February, but it may be a bit early to tell. The ensemble clusters also bring some pessimism to the pattern change with only 17% of solutions showing a trough over the Eastern Pacific, while the remainder hold on to the West Coast ridging signal. Fingers crossed the storm track can barrel some more meaningful precipitation into the West soon! -Edan && .AVIATION... VFR conditions and light surface winds continue for area TAF sites through tonight. Freezing fog has a 10-15% chance to form again tomorrow morning at KTRK, but the upper level clouds may win out and disturb its formation like this morning. Haze and poor mixing will lead to reduced slantwise visibility early Thursday, but there is potential for improved mixing by late afternoon. A quick system moves through Thursday, delivering 20-30% chances for a light rain shower for KMMH. Increased FL100 winds Friday into Saturday will result in bumpy flying conditions through early Sunday morning. -Edan && .REV Watches/Warnings/Advisories... NV...None. CA...None. && $$

193 FXUS66 KSTO 212044 AFDSTO Area Forecast Discussion National Weather Service Sacramento CA 1244 PM PST Wed Jan 21 2026 .KEY MESSAGES... - Valley low clouds/fog potential through Thursday. Slight (10-20%) chance for isolated light mountain shower tonight (1/21/2026). - Fog potential diminishes Friday-Sunday as north to northeast winds increase Friday night into Saturday. Strongest gusts over the mountains. - Dry weather prevails this weekend, followed by renewed fog potential early next week. && .DISCUSSION... ...Today Through Thursday... GOES-West visible satellite imagery depicts a swath of low clouds across the Valley this afternoon with scattered mid to high level clouds aloft as an upper low approaches southern California. Visibilities are steadily improving and as a result we`ve allowed the Dense Fog Advisory to expire at noon. However, isolated areas of fog are still being observed across portions of the Valley this afternoon. Fog redevelopment is expected tonight into tomorrow morning, but conditions are slightly less favorable as an upper low approaching southern California disrupts ridging aloft and introduces increased mid/high cloud cover. Probabilities for visibilities 0.5 mile or less are 20 to 40% throughout the Valley, with the highest probabilities in the southern Sacramento Valley. Remember to use low-beam headlights when driving through fog, exercise caution, and slow down. As the aforementioned system approaches SoCal, attendant moisture may yield an isolated mountain shower over the Sierra this evening. Although probabilities of 0.10 or more are only around 10-20%. ...Friday-Early Next Week... The upper low will trek across southern California Friday into the weekend, weakening upper ridging and initiating an offshore flow pattern. As a result, north to northeast winds increase Friday night into Saturday. The strongest winds are expected over the Sierra and along the western portion of the Sacramento Valley (I-5 and westward) where probabilities of gusts greater than 30 mph are 50 to 70%. Relative humidities trend lower over the weekend as well, primarily over the mountains, foothills, and northern Sacramento Valley. No precipitation is expected with this weekend as probabilities have once again trended down. Conditions for widespread fog are less favorable Friday through the weekend as a result of these north to northeast winds. However, as ridging builds back in early next week the potential for Valley low clouds/fog returns. && .AVIATION... Lingering patchy MVFR/IFR conditions in central/southern Sacramento Valley, Delta, and northern San Joaquin Valley through 21z Wednesday. FG/BR expected to re-develop after 03z-06z Thursday with similar aerial extent as today except coverage will be patchier in the northern Sacramento Valley. Surface winds will be below 12 kts. && .STO WATCHES/WARNINGS/ADVISORIES... None. && $$

406 FXUS65 KMSO 212128 AFDMSO Area Forecast Discussion National Weather Service Missoula MT 228 PM MST Wed Jan 21 2026 .DISCUSSION... KEY MESSAGES: - Strong valley inversions and fog/stratus linger into Thursday, especially in north central Idaho. - Coldest air of the winter thus far begins to filter into the region Thursday through Friday. Cold wind chills around 10 below zero in northwest Montana and along the Continental Divide Friday morning. Fog and low clouds remain trapped in the valleys of northwest Montana and north central Idaho today. Overall we anticipate this cloud cover will begin to lift overnight tonight into Thursday morning as a colder airmass from Canada begins to spill over the Continental Divide. North central Idaho will be the last to see clearing, most likely not until later in the day Thursday. Breezy northeast to east winds will develop Thursday with the beginning of the arctic spillover, though not overly strong with exposed areas generally seeing winds between 20 to 30 mph through Thursday. Due to the airmass dropping out of Continental areas in Canada, there is little moisture for this front to work with, thus conditions will be mainly dry. Much colder air, the coldest we have seen so far this winter, will filter into western Montana and north central Idaho Friday into Saturday. While not record-breaking cold by January standards, the mild winter we have had of late will make this feel like a significant change. The coldest air is anticipated across northwest Montana and along the Continental Divide where single digits to even below zero temperatures will be observed. Falling temperatures will overlap with wind late Thursday night into Friday morning to produce wind chills as low as -5 to -15 degrees below zero. Winds will relax during the day Friday, with many valleys likely seeing the coldest temperatures Saturday morning, depending on cloud cover. Temperatures will slowly moderate Sunday into early next week. Forecast models continue to show a weak disturbance overrunning the colder air in place in the Monday/Tuesday timeframe. Seventy- five percent of models show this as a very light precipitation event with minimal accumulations. However, around 25 percent show somewhat higher amounts (2 to 4 inches snowfall), which could lead to some minor impacts due to accumulating snow, especially over mountain passes along the Idaho/western Montana border. Eighty percent of forecast models show the ridge of high pressure building back over the region by Wednesday next week, allowing strong inversions to redevelop with the threat of fog and/or low stratus. && .AVIATION...Low stratus and pockets of fog remain locked in across northwest Montana and the lower valleys of north central Idaho. Obscured terrain will be the main concern with the lower cloud deck. As an arctic airmass drops south out of Canada, it will begin to increase a northeasterly pressure gradient, first across northwest Montana after 22/1200z and then into the rest of western Montana between 22/1500z to 22/1800z. Wind gusting up to 25kts in exposed locations will be possible, including at KGPI. This increased wind should help raise the cloud deck, other than perhaps through north central Idaho, where the easterly gradient won`t really materialize until after 23/0000z. This air mass is relatively dry and thus widespread precipitation is not anticipated. && .MSO WATCHES/WARNINGS/ADVISORIES... MT...None. ID...None. && $$

953 FXUS65 KBOI 220352 AFDBOI Area Forecast Discussion National Weather Service Boise ID 852 PM MST Wed Jan 21 2026 .DISCUSSION...Some of the stratus deck did erode this afternoon, from eastern Ada County through the Western Magic Valley. However, widespread stratus remains entrenched in the remaining valleys of southwest Idaho and southeast Oregon generally below 5000 feet MSL. While ceilings lifted slightly this afternoon, observation trends indicate a lowering of cloud bases this evening. Stratus will return across the Upper Treasure and Western Magic Valley overnight. Before that happens, temperatures will cool quicker but will level off once the stratus is in place again. The mountains will see mostly clear skies tonight into Thursday with mild daytime temperatures. The current forecast has this covered well so no updates needed at this time. && .AVIATION...MVFR-IFR in the Treasure Valley terminals this evening in low stratus. IFR-LIFR conditions in very low stratus/fog overnight near KBNO-KBKE-KMYL and KTWF-KJER. VFR elsewhere and briefly tomorrow afternoon in higher elevations with clearing. Surface winds variable 8 kt or less. Winds at 10kft: W-NW 10-20 kt. KBOI...MVFR this evening with intermittent IFR as the stratus cloud deck lowers overnight. Ceilings improving to MVFR late tomorrow morning. Surface winds NW 3-5 kt becoming SE 3-6 kt overnight then variable less than 5 kt early tomorrow morning. && .AIR STAGNATION...Stagnant conditions continue this evening across the lower valleys due to the persistent strong temperature inversion and light winds. Mixing height observations support the continuation of the Air Stagnation Advisory through early Friday morning. The incoming cold front on Friday is expected to provide enough vertical mixing and increased transport winds to clear out the stagnant air mass, bringing improved air quality for the weekend. && .PREV DISCUSSION... SHORT TERM...Tonight through Friday night...Still overcast in the valleys below 5000 feet MSL but several degrees warmer than yesterday, and cloud ceilings are higher. There`s also less fog in the valleys. Even so, persistence remains the main theme through early Friday. On Friday a dry surface cold front supported by an upper level short wave trough will come in from the north. That system will weaken if not break the inversion for a day or two, while light to moderate northwest surface winds provide enough vertical mixing to end the Air Stagnation Advisory. Friday night will be colder, especially aloft, and dry enough to decrease the stratus in the valleys. LONG TERM...Saturday through Wednesday...Dry conditions will continue Saturday and Sunday as the back end of a trough brings a northwest flow over the region. The cooler air aloft may help break up the valley inversions and fog early Saturday, and gradually warm up valley temperatures this weekend through Wednesday. A weak ridge will build in Sunday through Monday, possibly returning a temperature inversion. A weak trough will dig across the upper Rockies late Monday through early Tuesday, likely bringing light snow over the central mountains of eastern OR and western ID Monday. A well defined ridge will build into the region by Wednesday, sustaining drier conditions and returning the possibility of valley inversions by midweek. && .BOI WATCHES/WARNINGS/ADVISORIES... ID...Air Stagnation Advisory until 5 AM MST Friday IDZ011>014-016-028-033. OR...Air Stagnation Advisory until 5 AM MST /4 AM PST/ Friday ORZ061>064. && $$ www.weather.gov/Boise Interact with us via social media: www.facebook.com/NWSBoise www.x.com/NWSBoise DISCUSSION...JDS AVIATION.....SA AIR STAGNATION...JDS SHORT TERM...LC LONG TERM....JY

756 FXUS65 KLKN 212119 AFDLKN Area Forecast Discussion National Weather Service Elko NV 119 PM PST Wed Jan 21 2026 .KEY MESSAGES... Updated at 110 PM PST Wed Jan 21 2026 * Dry weather will persist through at least Thursday * High temperatures well above seasonal values each afternoon through Thursday * A weak weather system will usher in cooler temperatures for the weekend with upper ridging building back in for next week && .DISCUSSION... (This afternoon through next Wednesday) WEATHER PATTERN OVERVIEW: A large and deep upper level low pressure system can be seen just west of Hudson Bay in Canada at this time. Meanwhile, upper ridging continues to hold firm across the western United States. This upper ridge will gradually move west, allowing for a closed low to move southeast across southern California. This system will trek east across northern Mexico for Friday and Saturday as a cold front pushes through the area. For tonight, expect another night of temperatures in the teens and 20s with no precipitation expected. On Thursday and Thursday night, the upper ridge will be squeezed to the west by a closed upper trough in the eastern Pacific. A mix of clouds and sun are expected tomorrow under mainly dry conditions. High temperatures will once again be in the 40s and 50s with light winds and no precipitation expected during the day. Expect partly to mostly cloudy skies Thursday night with energy moving southward along the western edge of the aforementioned long wave trough late Thursday into Friday morning. Isolated, light snow showers are expected to develop across east-central Nevada with very little in the way of accumulation. Overnight lows will be in the 20s. The flow will gradually shift to the north Friday and Saturday. Winds are expected to shift to the north late Friday morning into the afternoon with gusts to 30 mph, especially along the high terrain. High temperatures are expected to remain above normal though they will be several degrees cooler versus Thursday afternoon with readings in the 40s. Isolated, light showers are expected across portions of US Highway 50 in Eureka and White Pine counties, though amounts will be light at less than a half inch. Winds will be breezy out of the north but gusts are expected to be limited to 20 mph. Skies are expected to scatter out during the overnight through Saturday morning with colder temperatures expected. Lows will be in the single digits and teens. Highs on Saturday will be in the 30s and 40s, which will be at or just below normal values for a change. Saturday night through Wednesday, the weather is expected to go back to a more quiet pattern during this time frame with light winds. Afternoon highs will once again warm to above normal conditions by early next week with readings in the 40s and 50s. Overnight lows will be in the teens and 20s. FORECAST CONFIDENCE & DEVIATIONS: Confidence remains high on the forecast pertaining to dry weather continuing through tomorrow. High temperature forecast also remains high with well above seasonal values tomorrow. Forecast confidence diminishes to moderate regarding the system transiting the region Friday and Saturday. Only deviation made from the NBM model output is the overnight low temperatures, which was massaged down a few degrees from the forecast. && .AVIATION... Look for VFR conditions and light winds through the upcoming 24 hour period. && .LKN Watches/Warnings/Advisories... None. && $$ DISCUSSION...86 AVIATION...99