683 FXUS66 KSEW 130321 AFDSEW Area Forecast Discussion National Weather Service Seattle WA 821 PM PDT Mon Oct 12 2026 .UPDATE... Mid to high level cloud coverage is streaming overhead as an upper-level ridge noses into British Columbia. Excluding the development of patchy valley fog and areas of frost, benign conditions are expected tonight. No changes made in this evening`s forecast package. The previous discussion remains below along with an updated marine and aviation section. && .SYNOPSIS... A weather system moving into British Columbia will brush western Washington on Tuesday, bringing showers to the Pacific coast and the North Interior into Wednesday. A ridge of high pressure will rebuild over the area Wednesday into Thursday, before pushing inland on Friday. Warm temperatures are expected Thursday and Friday as offshore flow develops. A weak system will move into the area on Saturday, followed by a stronger system Sunday into Monday. && .SHORT TERM /TONIGHT THROUGH WEDNESDAY NIGHT/... Satellite imagery shows sunny and clear skies across western Washington this afternoon, with areas of patchy fog this morning having dissipated. Highs are still on track to be close to seasonal norms today, and are expected to top out in the upper 50s to mid 60s across the area. Dry conditions will continue into tonight as an upper level ridge over the region flattens. A weather system moving into British Columbia tonight into Tuesday will bring increasing mid to high cloud cover to the area overnight, bringing warmer overnight low temperatures to much of western Washington and limiting the potential for fog and frost formation overnight. Overnight lows are expected to be in the upper 30s to mid 40s. The system moving into British Columbia will brush western Washington Tuesday into early Wednesday as the ridge continues to weaken and the system sags southward. This will bring some light shower activity to the northwestern portion of the area- mainly to the Pacific Coast, the western slopes of the Olympics, and areas from King County northward. Overall rainfall amounts will be rather light, with areas across the Northern Interior likely only getting a few hundredths of an inch of rain. The highest amounts will be along the North Coast, where generally a quarter of an inch to half an inch of rain will be possible. Highs on Tuesday will be in the mid 50s to mid 60s. An upper level ridge will then build back into the Pacific Northwest on Wednesday, with showers expected to taper throughout the day. Highs are expected to be in the lower to mid 60s across western Washington with mostly cloudy conditions in the morning becoming partly cloudy by the afternoon hours. && .LONG TERM /THURSDAY THROUGH MONDAY/... Guidance remains in strong agreement with the upper level ridge building over the region on Thursday. A thermal trough will also build northward along the coast and will turn the low level flow offshore, helping to warm afternoon highs into the mid 60s to mid 70s across the area. Friday will be the warmest day of the week as the ridge axis pushes further inland and offshore flow persists through the morning hours. Highs will climb a degree or two and are again expected to be in the mid 60s to mid 70s- roughly 5 to 10 degrees above normal across the area. Overnight lows both Thursday and Friday will be in the mid 40s to low 50s. A dissipating frontal system then looks to move into the area on Saturday as the ridge axis pushes further to the east. The best chances for rain remain along the Pacific Coast and across the North Cascades as the system moves over the area. A stronger, more organized frontal system then looks to move through the region Sunday into Monday, bringing more widespread chances of rain and breezy winds to western Washington. A dusting of snow for the higher peaks will also be possible on Monday as snow levels drop to 5000-5500 ft. Highs will cool over the weekend as conditions become more unsettled and only look to top out in the upper 50s to mid 60s. Overnight lows will generally be in the 40s and 50s. 14 && .AVIATION... Widespread VFR this evening with increasing high clouds from the northwest. Ceilings will gradually deteriorate along the coastline overnight into early Tuesday morning, with MVFR ceilings expected along the coast by the afternoon Tuesday. Otherwise, interior terminals expected to remain VFR with high clouds expected to limit fog development in the morning. Light northerly surface winds this evening will shift southerly by Tuesday morning and will remain light through the afternoon. KSEA...VFR with increasing cloud cover tonight, expected to limit fog development and keep conditions VFR into Tuesday. Increasing chances for MVFR ceilings developing early Wednesday morning. Generally light and variable winds this evening will shift southeasterly by 06Z this evening. && .MARINE... A weak surface ridge will shift inland on Tuesday as a frontal system approaches the offshore waters with winds shifting to the E/SE across much of the waters. A weak cold front will reach the area on Wednesday with possible headlines for low end small craft advisory winds across portions of the coastal waters and the west entrance to the Strait of Juan de Fuca. High pressure rebuilds across the waters on Thursday with the flow turning northerly or weakly offshore as thermally induced low pressure expands northward across western Oregon. Another front is expected to reach the waters Friday night or Saturday with possible headlines for winds and/or steepening seas across the coastal waters. Additionally, guidance indicates possible headlines for the Strait on Saturday with gusts having a 50-60% chance of reaching small craft thresholds. Seas will remain around 4 to 7 feet throughout much of the week before building to 8 to 11 feet by Sunday and remaining elevated into early next week. 15 && .SEW WATCHES/WARNINGS/ADVISORIES... WA...None. PZ...None. && $$

036 FXUS66 KPQR 122033 AFDPQR Area Forecast Discussion National Weather Service Portland OR 133 PM PDT Mon Oct 12 2026 .SYNOPSIS...Dry weather continues through the workweek as high pressure strengthens over the Pacific Northwest. Frost remains a concern across interior valleys tonight, followed by a warming trend late in the week as ridging amplifies and easterly flow develops. A return to cooler, wetter conditions is possible over the weekend as a trough approaches from the Gulf of Alaska. && .DISCUSSION...Now through Sunday...High pressure will maintain generally quiet weather across northwest Oregon and southwest Washington through midweek. An upper-level low over eastern Oregon and Washington continues to weaken and shift south, while ridging builds inland from the northeast Pacific. Afternoon temperatures will gradually recover from the mid 60s today and Tuesday into the lower 70s Wednesday. The primary near-term concern is another round of frost tonight as clear skies and light winds favor efficient radiational cooling. Interior valleys away from urban centers are expected to see temperatures fall into the mid 30s, with colder sheltered locations potentially approaching freezing. Frost Advisories have been issued for portions of northwest and west central Oregon and southwest Washington for tonight into Tuesday morning. Temperatures within the Portland metro should remain somewhat milder due to the urban heat island effect. Additionally, the Upper Hood River Valley is expected to see sub-freezing temperatures as low as 28 to 32 degrees, therefore a Freeze Warning has been issued from tonight into Tuesday morning. Expect the coldest temperatures near Parkdale. Frost and freeze conditions could kill crops, other sensitive vegetation and possibly damage unprotected outdoor plumbing. Consider temporarily covering sensitive outdoor plants with a lightweight cotton fabric (such as bed sheets, thin blankets), as this will help retain heat and provide frost protection for your plants. Dry conditions are expected to persist through Wednesday for most of the forecast area. A weak system tracking along the northern periphery of the ridge toward British Columbia may bring a light chance of light showers to the south Washington coast Wednesday morning, but precipitation is not expected elsewhere. Frost potential should decrease after tonight as increasing cloud cover and a gradual change in the low-level wind pattern support milder overnight temperatures. The upper-level ridge is forecast to strengthen further Thursday and Friday, allowing temperatures to climb into the mid to upper 70s across the interior lowlands. Thermal troughing is also expected to redevelop, bringing a return of easterly offshore flow through the Columbia River Gorge and Cascade gaps late in the week. While the Columbia River Gorge will likely stay gusty through each day, winds in the Cascades will likely weaken by the afternoon each day, followed by strengthening again overnight. The strength of this flow will need to be monitored as the pattern evolves. Heading into the weekend, guidance increasingly favors an upper-level trough moving southeast from the Gulf of Alaska and displacing the ridge eastward. This would bring cooler temperatures and a renewed chance for precipitation across the region, potentially extending into early next week. Probabilistic guidance suggests a decent amount of rain over the weekend, with chances of 0.25 inches over 48 hours around 25-50% along the coast, 20-30% within the interior lowlands, and 15-30% over the Cascades. As for chances of 0.01 inches, 40-70% along the coast, 40-60% within the interior lowlands, and 30-60% over the Cascades. With considerable uncertainty in the timing, strength, and placement of the trough, confidence in the details of the weekend forecast remains limited. ~12 && .AVIATION...Through 18Z Tuesday...High pressure will maintain VFR conditions with clear skies through the TAF period for most locations. There`s a 15-25% chance of localized areas of stratus with MVFR/IFR conditions forming again around 11-14z Tue for inland valleys and along the coast with the highest chances in the Portland area. Not enough confidence to add to the TAFs at the moment, but something to keep an eye on. Any stratus that does form should dissipate and improve to VFR by 16-18z Tue. However, a weak front brushing the PacNW will bring increased high level cloud cover from the NW after 10-12z Tue. Depending on the timing of these clouds, this could impact stratus development Tuesday morning. Northwesterly winds this afternoon around 5-7 kt or less, becoming light and variable after 02-04z Tue. KPDX AND APPROACHES...VFR through the TAF period, though there`s a 15-25% chance of MVFR/IFR stratus forming Tuesday morning between 11-14z. If this stratus does form, it should dissipate by 16-18z Tue. Northwesterly winds under 5 kt. -03 && .MARINE...Benign marine conditions expected this week. A Small Craft Advisory is in effect for the main channel of the Columbia River Bar from 4-9 PM this evening for a strong ebb current bringing seas to 6-7 ft. Otherwise, high pressure will maintain light northerly winds across the waters through tonight. Tuesday to Wednesday, winds turn more southerly from a weak front, then return northerly by the end of the week. Seas remain around 4-6 ft this week with periods of 13-16 seconds through Wednesday and 10-13 seconds late this week into the weekend. A long-period west/northwesterly swell will result in a moderate threat for sneaker waves this week. Caution should be used when in or near the water. -10/03 && .PQR WATCHES/WARNINGS/ADVISORIES... OR...Frost Advisory from midnight tonight to 8 AM PDT Tuesday for ORZ102>109-112>119-123>125. Freeze Warning from midnight tonight to 8 AM PDT Tuesday for ORZ121. WA...Frost Advisory from midnight tonight to 8 AM PDT Tuesday for WAZ202-204>208. PZ...Small Craft Advisory from 4 PM this afternoon to 9 PM PDT this evening for PZZ210. && $$ www.weather.gov/portland Interact with us via social media: www.facebook.com/NWSPortland x.com/NWSPortland

616 FXUS66 KMFR 130512 AFDMFR Area Forecast Discussion National Weather Service Medford OR 1012 PM PDT Mon Oct 12 2026 ...New Aviation Section... .AVIATION (06Z TAFs)... There is still some uncertainty whether or not low clouds will form along/near the coast impacting KOTH overnight into Tuesday morning. That said, went with satellite trends and model consensus resulting in VFR conditions through this TAF cycle. Inland TAF sites have a clearer picture with high confidence for a VFR cycle. High clouds will likely infiltrate the region through the TAF cycle. Lastly, expecting overall light diurnal wind speeds through this cycle. -Guerrero && .PREV DISCUSSION... /Issued 424 PM PDT Mon Oct 12 2026/ AVIATION (00Z TAFs)... The forecast along the coast may be difficult tonight with regards to low clouds impacting KOTH. There may be enough offshore flow to keep LIFR/IFR ceilings from developing tonight, but confidence was higher to include these low ceilings and will maintain these LIFR/IFR conditions through much of the morning hours. Satellite observations over the next few hours will be very telling and may amend or include in subsequent TAFs if necessary. Otherwise, expecting mostly clear skies and VFR conditions for inland TAFs with overall light diurnal wind speeds. -Guerrero PREV DISCUSSION... /Issued 102 PM PDT Mon Oct 12 2026/ KEY MESSAGES... * Frost and freezing temperatures will develop this morning and again Tuesday morning. * High pressure builds overhead for the rest of the week with highs peaking late week about 10 to 15 degrees above normal. * A mostly dry cold front arrives with cooler temperatures this weekend. * Precipitation chances are looking more likely early next week. DISCUSSION...Today will be the last cooler than normal day, then temperatures will warm through the rest of the week as high pressure builds in overhead. Another round of near-freezing temperatures is expected in the valleys west of the Cascades tonight. The Shasta and Scott valleys in Siskiyou County dropped well below breezing, and therefore will have no more frost/freeze headlines this season. In oregon, some light winds early this morning kept temperatures from dropping as low as expected for some locations, such as at the Medford airport, while locations with calm winds did drop as forecast. As a result, frost and freezing conditions were more spotty and coverage was far from uniform. With temperatures expected to be a few degrees warmer tonight, and with those spotty frost/freeze conditions last night, have opted to issue frost advisories for the inland valleys west of the Cascades to ensure all areas are covered, just in case. It should be noted that the average date of the first freeze for the Illinois, Applegate, and Rogue valleys occurs during the second week of October. As such, after this round of cold temperatures, these areas may not need additional headlines. The Umpqua Basin, however, typically does not reach the first freeze until early November. The upper trough that has brought us these cold temperatures will gradually edge southward into NW Nevada late tonight and eventually into Utah by Tuesday. Upper ridging then develops and amplifies over the area during the rest of this week, resulting in a warming trend that will culminate Thursday and Friday with temperatures around 10 to 15 degrees above normal for mid-October. Temperatures will see another cooldown this weekend with the arrival of a mostly dry cold front. Another front, associated with a much deeper and stronger upper-level trough, then arrives early next week with a much higher chance of widespread precipitation. And with the cooler, more seasonable temperatures in place by that time, there is a chance for some snow in the higher mountains. AVIATION...12/18Z TAFs...VFR levels look to continue across northern California and southern Oregon through much of the day. Marine stratus looks to bring IFR/LIFR levels to parts of the coast this evening, with that layer possibly lasting through most of the TAF period before clearing on Tuesday morning. A brief period of IFR/LIFR levels may also develop at the Roseburg terminal early Tuesday morning as well, but would likely clear out within a few hours. -TAD MARINE...Updated 1230 PM PDT Sunday, October 12, 2026...Gusty north winds and steep to very steep wind-driven seas will continue across the area into Tuesday. Winds will be strongest and seas will be highest south of Port Orford. Furthermore, long period west- northwest swell will continue into this afternoon. Improved conditions are expected Tuesday night, but only for a brief period before the thermal trough reforms and gusty north winds return to areas south of Port Orford on Wednesday. && .MFR WATCHES/WARNINGS/ADVISORIES... OR...Frost Advisory from 2 AM to 9 AM PDT Tuesday for ORZ023-024-026. CA...None. PACIFIC COASTAL WATERS...Small Craft Advisory until 11 PM PDT Wednesday for PZZ350-356-370-376. Hazardous Seas Warning until 11 PM PDT this evening for PZZ356- 376. && $$

633 FXUS66 KEKA 122100 AFDEKA AREA FORECAST DISCUSSION National Weather Service Eureka CA 200 PM PDT Mon Oct 12 2026 .KEY MESSAGES... * Another cold morning is expected Tuesday with areas of frost and freezing potential. * Dry conditions will lead to areas of low relative humidities through the week. * A warming trend is expected to impact the area through the week into the weekend, peaking on Friday. && .SYNOPSIS...Clear skies and seasonable temperatures are expected today. Another chilly morning is forecast for Tuesday morning with areas of Frost and Freezing potential. A warming trend will increase temperatures through the week. && .DISCUSSION...Last weekend, a cold front brought cooler and dry air to the area. This system disrupted the marine layer allowing for clear skies at the coast through early this week as steady light offshore winds overnight continue. Clear skies and light wind will allow for uninterrupted cooling in the valley floors. Frost Advisories and Freeze Warnings have already been issued for many interior valleys from 1 A.M. through 8 A.M. Tuesday morning. Wednesday night should be warm enough to have much less impacts from cooler temperatures as temperatures could struggle to reach or go below 32F. Through the week, a slight warming trend will take effect due to a building upper level ridge. This weather pattern will result in calm, chilly conditions with building winds in the afternoon as daytime heating takes effect. Inland heating is likely to peak Thursday and Friday with valleys reaching the high 80s to low 90s again. Winds will be mostly terrain driven with upslope - upvalley flow. Relative Humidities will reach a minimum late week with widespread areas of RH values <20%. however, winds ware likely to remain terrain-driven and light to moderate late week. This coming Sunday into next Monday, Ensemble clusters show an upper level trough and an associated cold front entering the area. Both the GEFS and EPS support this as well. This system is 7days out and could change substantially through the week. Most of this system`s rain would fall in the northern counties of Del Norte, Humboldt, and Trinity where some of the highest ridges above 4000ft could see very light snow whereas Mendocino and Lake counties are more likely to see moderate to strong NW winds if this system remains on track. This system is capable of changing and updates can be expected through the week. DS && .AVIATION...18Z UPDATE...VFR Conditions are expected to be widespread today for all terminals in NW CA. Gusty northerly winds are expected at coastal terminals and within river valleys near the coast. Inland terminals can expect terrain-driven upslope/upvalley winds, yet gusts are not expected to be widespread. Winds will calm near sunset with continued VFR ceilings through the night. Very shallow ground fog is possible, yet minimal impacts are expected at this time. DS && .MARINE...Gale force winds have decreased through the morning leading to wave heights decreasing sooner than expected. Widespread small craft advisories remain as waves continue to be steep. A fairly sizable NW swell has also entered the waters which is currently being recorded at 7ft @ 17s. Moderate to fresh breezes are likely to develop leading to a continued lowering of short period seas and the overall sea state. This NW swell is likely to wane to 4-5ft and mix with a S swell of 3-4ft through the week. DS && .FIRE WEATHER...Multiple days of cool but dry air has lowered ERC values. Much weaker, terrain-driven winds and an increasingly stable atmosphere in the coming days will help greatly reduce overall fire danger. However, dry conditions are expected through the week (around 20% RH each day) with worsening overnight recoveries through Thursday as midslope thermal belts develop. Smoke transport will also worsen through the week for any fires that do start. More moist air is expected to push across the area this weekend with a potential for very breezy conditions in Mendocino and Lake county late this weekend into early next week. DS && .BEACH HAZARDS...A long period swell currently up to about 7 feet at 17 seconds will persist through the day Monday. As short period seas begin to fall, this swell will provide and increasing sneaker wave risk through the day. The swell will begin to decay Tuesday. The sneaker wave risk will lessen as the swell decays, but will remain through midweek especially as short period seas calm. The highest risk is expected during periods of incoming tides. With high tides along the California coast at around 11am to 1pm. A positive tidal anomaly is yielding tides around 1-1.2 feet higher than predictions on top of higher than usual tides, adding to the threat. /JHW && .EKA WATCHES/WARNINGS/ADVISORIES... CA... Beach Hazards Statement until 10 PM PDT this evening for CAZ101-103-104-109. Frost Advisory from 1 AM to 8 AM PDT Tuesday for CAZ103-104- 106-108>111-114-116>118. Freeze Warning from 1 AM to 8 AM PDT Tuesday for CAZ108-110- 111-114-116-117. NORTHWEST CALIFORNIA COASTAL WATERS... Small Craft Advisory until 3 AM PDT Tuesday for PZZ450-455. Small Craft Advisory until noon PDT Tuesday 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

737 FXUS66 KMTR 130448 AFDMTR Area Forecast Discussion National Weather Service San Francisco CA 948 PM PDT Mon Oct 12 2026 ...New AVIATION, MARINE... .KEY MESSAGES... Updated at 118 PM PDT Mon Oct 12 2026 - Cooler weather through tomorrow; warming trend and above normal temperatures starting mid to late week - Coastal flooding during high tides through midweek - Hazardous beach conditions through this evening due to sneaker waves, rip currents, and breaking waves - Elevated fire weather conditions mid to late week for higher elevations && .SHORT TERM... Issued at 118 PM PDT Mon Oct 12 2026 (This evening through Tuesday night) An upper level trough dominates much of the West Coast`s weather this afternoon as the closed low sits over the PacNW and broad troughing extends southward through California. To it`s west, over the eastern Pacific, high pressure is being observed. Satellite imagery shows these too features quite well, with visible satellite showing the base of the trough over Central and Southern California. Most of our skies this afternoon remain clear; however, if you`re in the interior Central Coast region, you may see some small puffs of cumulus clouds building over the ridges. So far there hasn`t been any measurable rain reported or observed, likely due to the dry air in place and limited cloud growth. Tonight, look for skies to clear and for another chilly fall night. Temperatures should generally similar to or a few degrees higher than last night. Tuesday`s forecast will be similar to today, though skies across the region should be mostly clear with high temperatures being a few degrees warmer than today. && .LONG TERM... Issued at 118 PM PDT Mon Oct 12 2026 (Wednesday through next Sunday) An upper level high pressure system over the eastern Pacific will continue to build and expand eastward towards the West Coast. This will help push the upper level trough out of the region late Tuesday into Wednesday. During this time frame we will see a period of offshore flow during the overnight hours. As the high continues to build and the low moves east, each night will bring a renewed chance of these offshore winds. Especially late in the week, as the upper level trough elongates and then splits. When this occurs, the trough situates over the Desert Southwest and around southern California. Ridging remains over the northern half of the state which should lead to an increase of offshore flow and our warming trend. Ensembles and models then show signals of quasi-zonal flow and weak ridging for the weekend. Temperatures should decrease in response to the pattern change. For fire weather concerns, please see the fire weather discussion below. && .AVIATION... (06Z TAFS) Issued at 948 PM PDT Mon Oct 12 2026 Generally VFR conditions prevail with the exception of patchy MVFR stratus, sea spray and haze along the immediate coast and a low confidence for radiational fog at STS early Tuesday morning. Light winds will continue through the night into the morning before gentle to moderate winds resume Tuesday afternoon, with a more northwest to west flow in the coastal areas to a more northerly breeze in the interior. Vicinity of SFO... VFR at the terminal through the TAF period. Gentle northwest flow will continue into the overnight period, with light offshore flow developing Tuesday morning before the northwest winds resume in the afternoon. SFO Bridge Approach... Similar to SFO. Monterey Bay Terminals... Moderate to high confidence of VFR through the TAF period. Light drainage winds persist into Tuesday morning before gentle to moderate northwest winds resume in the afternoon. && .MARINE... (Tonight through next Sunday) Issued at 948 PM PDT Mon Oct 12 2026 Gentle to fresh northerly breezes persist over the coastal waters through Friday. The strongest winds remain over the outer waters north of Point Reyes. The overall sea state will improve as well as the northwest swell diminishes. However, some moderate to longer period southerly swell mixes in through the week. && .FIRE WEATHER... Issued at 118 PM PDT Mon Oct 12 2026 There will be a few bursts of offshore winds this week, generally during the overnight hours. The first burst looks to occur tonight, particularly highlight the interior North Bay Mountains, where we could see gusts range from 20-35 mph, perhaps even up to 40 mph for the exposed ridges and the higher elevations. After that, the next area of concern we are monitoring is Wednesday night into Thursday morning, where the pressure gradient should be a bit more tight due to upper level wind patterns. Majority of the area should see offshore flow, in the north to northeast component , with gusts closer to 25-35 mph, locally higher perhaps up to 45 mph for exposed ridges, gaps, and passes. Warm and dry weather will be on tap as well, which will lead to an elevated threat for the higher terrain areas. Another round of offshore winds is expected Thursday night into Friday, but appears to be weaker than the previous two. && .BEACHES... Issued at 1031 AM PDT Mon Oct 12 2026 Compare to the last few days conditions along the coast are gradually improving as longer period swell trains are decreasing. However, buoy reports Monday morning continue to advertise moderate to longer period swells (albeit smaller heights) entering the coastal waters. As such, elevated surf zone conditions lingering. Additionally, moderate period west-northwest swell will arrive Monday afternoon lingering into Monday evening. As such, Beach Hazard Statement remains in effect through this evening. The large tidal swings will also result in coastal erosion as water and waves are brought farther up the beach than normal, especially during high tide. Remain off jetties, piers, rocks, and other waterside infrastructure as waves can sweep across the shoreline without warning, pulling people into the sea. Never turn your back on the ocean! MM && .MTR WATCHES/WARNINGS/ADVISORIES... CA...Beach Hazards Statement until 10 PM PDT this evening for CAZ006- 505-509-529-530. Coastal Flood Advisory until 3 PM PDT Tuesday for CAZ006-508-529- 530. Coastal Flood Advisory until 4 PM PDT Wednesday for CAZ506. PZ...Small Craft Advisory until 3 AM PDT Tuesday for Pt Arena to Pt Reyes 10-60 NM. && $$ SHORT TERM...KR LONG TERM....KR AVIATION...DialH 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

297 FXUS66 KOTX 130526 AFDOTX Area Forecast Discussion National Weather Service Spokane WA 1026 PM PDT Mon Oct 12 2026 .KEY MESSAGES... - Chilly overnight lows the next couple of mornings with widespread frost/freeze conditions. - Dry conditions, light winds, and moderating temperatures through the week. - Gusty westerly winds and cooler temperatures return next weekend. && .SYNOPSIS... Morning lows will be chilly and near to below freezing for most areas through Tuesday morning. Weather will be drier through the week with temperatures trending warmer. Active weather returns by the weekend and into early next week. && .DISCUSSION... Tuesday through Friday: Upper-level ridging builds across the region on Tuesday, initiating a modest warming trend. A weak shortwave temporarily flattens the ridge on Wednesday, bringing increased cloud cover and a slight (~15%) chance of showers along the Cascade crest. While some models suggest precipitation may reach the surface across the Okanogan Highlands, but very dry mid-levels and weak dynamics leads to very low confidence in these solutions. The ridge amplifies Thursday into Friday as a surface thermal trough extends northward west of the Cascades, establishing light easterly to offshore flow. High temperatures will climb through the end of the work week, peaking in the mid 60s to lower 70s by Friday, which is roughly 10 to 15 degrees above seasonal normals. Overnight temperatures will remain chilly before moderating late in the week. Lows Wednesday morning will drop into the upper 20s to lower 30s across sheltered northern valleys and into the lower to mid 30s elsewhere, with milder conditions in the lower 40s near the Wenatchee area. Saturday through Monday: Ensembles have come into better agreement for the next weather system moving into the Pacific Northwest Saturday. This is rather weak with the wind forecast trending down over the last couple of days and the best precipitation chances remain at and west of the Cascade crest. This opens the door, however, for a deeper trough to move into the Pacific Northwest early next week. While ensembles generally favor this deeper trough moving into the western US, there remains some notable differences. 71% of ensemble members depict the trough shifting inland, delivering cooler temperatures and widespread precipitation chances to the Inland Northwest. Another 21% show the trough digging offshore along the California coast, which would allow ridging to continue and keep warmer, drier conditions in place longer. The remaining 8% suggest a weaker, progressive wave with minimal impact. Latest National Blend of Models (NBM) guidance reflects the dominant scenario with 24-hour precipitation chances exceeding 0.10 inches between 5 PM Monday and 5 PM Tuesday ranging from 40-60% over the mountains, 30-40% across eastern Washington and Idaho Panhandle valleys, and 15-25% across central Washington. /vmt && .AVIATION... 06Z TAFS: VFR conditions are expected as an upper-level ridge shifts into the Inland Northwest. Despite clear skies tonight, a dry boundary layer will inhibit fog development. High level clouds begin to increase from west to east early Tuesday morning, reaching north Idaho by Tuesday afternoon. Winds will be light through the period. FORECAST CONFIDENCE AND/OR ALTERNATE SCENARIOS: High confidence for VFR conditions through the period. ----------------------- 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 52 28 59 33 63 35 / 10 0 0 0 0 0 Coeur d`Alene 51 29 57 34 62 35 / 20 0 0 0 0 0 Pullman 47 27 57 32 62 36 / 30 0 0 0 0 0 Lewiston 53 33 60 36 66 39 / 50 0 0 0 0 0 Colville 59 23 60 27 65 30 / 0 0 0 0 0 0 Sandpoint 53 25 55 29 59 31 / 0 0 0 0 0 0 Kellogg 47 29 55 34 59 35 / 10 0 0 0 0 0 Moses Lake 59 29 62 33 67 36 / 0 0 0 0 0 0 Wenatchee 60 37 64 44 69 47 / 0 0 0 0 0 0 Omak 58 32 63 34 67 38 / 0 0 0 0 10 0 && .OTX WATCHES/WARNINGS/ADVISORIES... WA...Freeze Warning until 9 AM PDT Tuesday for Lower Garfield and Asotin Counties-Moses Lake Area-Okanogan Valley. ID...Freeze Warning until 9 AM PDT Tuesday for Lewiston Area. && $$

321 FXUS66 KPDT 130526 AFDPDT Area Forecast Discussion National Weather Service Pendleton OR 1026 PM PDT Mon Oct 12 2026 .KEY MESSAGES... - Cold morning temperatures continue through early week. *Freeze Warnings Issued* - Warming trend through the week, mountain showers late in week. && .DISCUSSION... Freeze Watches have been upgraded to Freeze Warning pretty much across the board, with some areas having much higher probabilities for sub-freezing temperature by Tuesday Morning (Grande Ronde Valley, Wallowa County, Blue Mt Foothills). The area will undergo clearing as a positively tilted ridge pushes across the PAC NW and Interior NW overnight. Winds throughout the Columbia Basin will be the lightest and that is where concern that probabilities might not be high enough for freezing. Light southerly winds across the central Oregon zones and foothills of the Oregon Blues, and light easterly to southeast winds round out the Tri-Cities and Foothills of the Blues in Washington. Through midweek, a gradual recovery of temperatures into the 70s for highs and above freezing upper 30s into the 40s for lows will be the trend. Potential for approaching 80 degrees returns per the NBM`s MaxT forecasts for the Foothills of the Blue Mts, the John Day Basin and central Oregon by Friday afternoon as breezy winds redevelop late week. From a clusters perspective the ensemble groups don`t seem to have large discrepancies in light precipitation amounts for the the days 7 and 8 period, but more timing whereas all of the clusters offer light (sub one tenth of an inch) of rain across the lower elevations vs in excess of one tenth across some of the the mountain zones Oct 19-22. && .AVIATION /06Z TAFS THROUGH 06Z WEDNESDAY/...VFR conditions to prevail through the period. Winds will be light, 12kts or less, and diurnally/terrain driven. Lawhorn/82 && .Preliminary Point Temps/PoPs... PDT 29 64 36 68 / 0 0 0 0 ALW 34 65 41 69 / 0 0 0 0 PSC 31 67 34 71 / 0 0 0 0 YKM 34 65 39 70 / 0 0 0 0 HRI 29 66 36 70 / 0 0 0 0 ELN 30 62 35 67 / 0 0 0 0 RDM 22 66 27 69 / 0 0 0 0 LGD 25 63 31 68 / 0 0 0 0 GCD 24 64 33 70 / 0 0 0 0 DLS 37 70 41 74 / 0 0 0 0 && .PDT WATCHES/WARNINGS/ADVISORIES... WA...Freeze Warning until 9 AM PDT Tuesday for WAZ026>029-521. OR...Freeze Warning until 9 AM PDT Tuesday for ORZ044-049-050-507- 508-510. && $$ DISCUSSION...71 AVIATION...82

965 FXUS65 KREV 122200 AFDREV Area Forecast Discussion National Weather Service Reno NV 300 PM PDT Mon Oct 12 2026 .KEY MESSAGES... * Cooler weather continues through Tuesday morning, with chilly overnight temperatures. * Valley rain showers and snow on the highest peaks are possible through Tuesday morning. * A gradual warming trend begins on Tuesday, with dry conditions and light afternoon breezes returning. && .DISCUSSION... For the rest of today going into tonight, model guidance shows an upper low over SE Oregon traveling down into central Nevada. With this pattern aloft today, cooler air continues to flow into the region from the north, which along with increased cloud cover over the region causes daytime high temperatures around 15-20 degrees below normal. Prepare for a cold night as well with W.Nevada seeing lows in the upper 20s to lower 30s range and Sierra communities being in the middle teens to lower 20s range. Remember to protect the 4 P`s from the cold: people, pets, plants, and pipes. As for precipitation chances, the latest run for the HRRR model shows shower chances increasing generally south of I-80 this afternoon and evening. Precipitation chances begin at 15-40% this afternoon and increase to 30-70% in the evening with the higher end chances seen in Mono and Mineral Counties. According to the latest run of the NBM, snow levels in the afternoon still look to be around 6500-7500 ft before dropping below 6000 ft around 8-11 PM in the Tahoe area and around 11 PM - 2 AM in Mono County. By Tuesday morning, snow levels will drop to around 4000-5000 ft in the Tahoe area and around 4500-5500 ft in Mono County. So expect valley rain and mountain snow with showers that occur today, with rain gradually turning to snow going into the night. Fortunately, the HRRR shows most shower chances fading around midnight tonight before the coldest temperatures arrive, though there may be some lingering showers south of US-50 into early Tuesday morning. Please be careful if traveling in the region tonight as any precipitation may make roads slick and wet surfaces may freeze when temperatures drop. Visibility could be reduced as well due to snowfall. As better moisture is well off to the east of our area, current QPF values with showers through tomorrow morning look to range between a trace and about 0.2 inches. The latest NBM probabilities show around a 20-50% chance of 1+ inch of snow in the highest peaks of the Sierra with the White Mountains seeing a 20-40% chance of 2+ inches. Lower elevations that see snowfall could receive a dusting to a few tenths of an inch if snow collects. There`s also less than 10% chance for a rumble of thunder within showers today, with thunderstorms that occur being capable of brief periods of heavy rainfall. On Tuesday, model guidance starts to show high pressure building over the region through the rest of the week as the upper low departs farther east. This signals a gradual warming trend with drier weather through the rest of the week, with daytime high temperatures across the region returning to near or above seasonal normals toward the weekend. Extended guidance does hint at a possible cooling trend at the start of next week. -078 && .AVIATION... Mostly VFR conditions continue with brief periods of MVFR conditions and mountain obscuration in the Sierra due to showers through around 13/06-07Z. KRNO/KCXP/KMEV/ see N/NW winds gusting up to around 25 kts through around 13/04-05Z when there is a 15-30% chance for isolated showers in the vicinity. KTVL sees a 20-40% chance for showers through 13/04Z as well. Portions of the Eastern Sierra (including KMCK) have a 35-65% chance through 13/07Z that will taper off completely by around 13/12Z. There also looks to be a 20-30% conditional chance of morning fog forming early Tuesday in the vicinity of KTRK should showers occur nearby today. By Tuesday afternoon, VFR conditions will prevail as a period of dry conditions begins along with a gradual warming trend. Sierra ridge winds may also gust up to around 50 kts on Tuesday afternoon. -078 && .REV Watches/Warnings/Advisories... NV...None. CA...None. && $$

328 FXUS66 KSTO 121929 AFDSTO Area Forecast Discussion National Weather Service Sacramento CA 1229 PM PDT Mon Oct 12 2026 For additional details on weather and expected impacts over the next 7 days, please visit weather.gov/sto/briefing. .KEY MESSAGES... - Cooler temperatures, mountain showers and isolated thunderstorms today. - Dry weather and below-normal temperatures on Tuesday, followed by drying and warming trend mid- to late next week. - Elevated Fire Weather conditions Tuesday in the Valley; potentially again on Thursday and Friday in northern Sac Valley & Mountains. && .DISCUSSION... ...Today & Tuesday... Mid-level clouds across foothills and mountains this morning, with some light returns noted on radar. Some accumulating rain showers and high elevations snow showers were observed overnight/early this morning as well as an upper level low north of the region influences the weather pattern over our area. Temperatures are fall-like this morning as well, with mid to upper 50s/low 60s across much of interior NorCal. Locally gusty north winds in the northern Sacramento Valley will continue today as well, as the low pressure continues to have a north to south pressure gradient over the Valley. For the rest of Monday, isolated mountain showers, high elevations snow showers (little to no additional accumulations), and a few isolated rumbles of thunder will be possible, but those chances are decreasing as we move through the rest of the morning. Tuesday we will continue to see more fall-like high temperatures across interior NorCal. Low pressure will begin to dig south into Nevada Tuesday as well, shifting the stronger north winds to the south and west into the Delta and Coast Range. Increased drying on the backside of the low pressure along with the breezier northerly winds will create elevated fire weather conditions in the northern Sacramento Valley and mountains Tuesday, with wind gusts of 20 to 30 mph and daytime humidity values in the teens to low 20s. Low pressure translates further east as we move through the rest of Tuesday. ...Wednesday-Saturday... By Wednesday, ensembles remain in good agreement that high pressure will begin to build in the Pacific. Warming trend, with drying conditions will remain in the forecast as we move through the work week. Pattern will once again result in breezy north to east winds across the region, ushering in the potential for elevated fire weather conditions for most of the region Thursday and Friday. Strongest winds look to be in the mountains, where downslope gusts of 25 to 45 mph are in the forecast now. Uncertainty remains in exactly how strong downslope winds will be, along with how low humidity values will be later this week. Temperatures will bounce back into the mid to upper 80s/90s by Wednesday and continue through at least Saturday. Long range ensembles showing the potential breakdown of the ridge by late weekend, early next week, which would at least usher in more fall- like high temperatures to the area. && .AVIATION... VFR conditions continue across much of interior NorCAL through 18z Tuesday. Light VFR precipitation possible south of Hwy 50 over the Sierra from now until 03z Tuesday. North winds 10 to 15 kts with gusts 20 to 30 kts until 06z Tuesday and lingering gusts along the west side of the Valley through 12z Tuesday. After 12z Tue, north winds return to across the Valley with 10 to 15 kts, up to 25 kts across the Delta through 18z Tuesday. For the mountains, breezy east winds develop after 03z Tuesday through 18z Tuesday with 10 to 20kts, gusting up to around 30 kts. && .STO WATCHES/WARNINGS/ADVISORIES... None. && $$

570 FXUS65 KMSO 121836 AFDMSO Area Forecast Discussion National Weather Service Missoula MT 1236 PM MDT Mon Oct 12 2026 .DISCUSSION... KEY MESSAGES: - Hard freeze coming for the mornings. - Valley fog and stratus will be common early this week. - A warming and drying trend this week. - Unsettled weather on the way for early next week. Satellite imagery early this afternoon indicates a closed circulation of low pressure over eastern Oregon and southwestern Idaho. This system, responsible for sending Pacific moisture northwards into southwest Montana and north-central Idaho, will take a more southern route going into Tuesday. It will take precipitation with it, leaving a positively tilted ridge of high pressure over the Northern Rockies. That ridge will strengthen throughout the week, bringing daytime temperatures up. Temperatures will peak on Saturday at about 10 degrees above normal. In the meantime, expect cold mornings with hard freezes likely in the valleys of western Montana and much of north-central Idaho. Those in the lower valleys of the Salmon and Clearwater rivers should still expect freezing temperatures, though only a few degrees off the freezing mark. Valley fog will be another hallmark of the ridge-following-snow scenario. Morning motorists and aviators should expect fog formation in the valleys. Ensembles are starting to agree on another low pressure system by early next week. Though most solutions are on board with a disturbance, some members bring the low south, some keep it as an open wave, and some show a closed low. At the current time horizon, we`ll let the reader chose their own adventure. && .AVIATION...Low ceilings are proving a challenge this afternoon at terminals that recorded precipitation, ie KBTM, KHRF, KSMN. Expect stratus to persist at those terminals this afternoon, generally keeping ceilings below 2,000 ft AGL. As high pressure begins to take over this evening, fog formation in the morning will become the next forecast challenge. Added fog into the 12/1800Z TAF for KBTM. Confidence is a little lower for the other TAF sites. Future TAF issuance may see fog added to KMSN, KHRF, and KMSO. && .MSO WATCHES/WARNINGS/ADVISORIES... MT...None. ID...None. && $$

105 FXUS65 KBOI 122355 AFDBOI Area Forecast Discussion National Weather Service Boise ID 555 PM MDT Mon Oct 12 2026 .UPDATE...Updated aviation discussion. && .KEY MESSAGES... - Unsettled conditions through early Tuesday, mainly on the Idaho side, with showers mainly over Magic Valley and Boise Mountains. - Cold morning temperatures tonight and Wednesday morning will bring patchy frost and near-freezing conditions, with Frost Advisories in effect for valley areas. - Warm and dry conditions Wednesday through next weekend. Temperatures reaching 10 degrees above normal by Friday. && .SHORT TERM /Through Wednesday Night/... Issued 202 PM MDT MON OCT 12 2026 The closed upper level low center is positioned directly over the region this afternoon. This system will continue to trigger scattered showers and isolated mountain snow showers, primarily across southwest Idaho through late this evening. Shower activity will gradually taper off from west to east overnight as the low weakens and kicks eastward toward the Rockies. Precipitation amounts will remain light, with valley locations picking up a few hundredths of an inch and higher elevations seeing less than an inch of light snow above 7000 feet. As shower activity diminishes overnight, clearing skies and light winds will allow for significant radiational cooling. Low temperatures tonight will fall into the lower to mid 30s across the lower valleys, with widespread 20s in the higher mountain valleys. Patchy frost is expected to develop late tonight into early Tuesday morning across the Treasure Valley and Western Magic Valley. Thus, a Frost Advisory has been issued for the Snake River Plain. Note that parts of the Magic Valley may avoid widespread frost tonight, as lingering clouds and showers through late morning could hold temperatures in the upper 30s. A weak ridge of high pressure builds overhead Tuesday and Wednesday, bringing dry conditions and a slight moderating trend in daytime highs. However, another cold morning is on tap for Wednesday morning under clear, calm conditions. Minimum temperatures Wednesday morning will mirror Tuesday morning, keeping the threat for localized frost and near-freezing valley temperatures intact before temperatures recover slightly Wednesday afternoon. A Frost Advisory has been issued for Wednesday morning, though a Freeze Warning may be needed from Mountain Home through the Magic Valley where temperatures could drop into the 30 to 33 degree range. Frost and Freezes are typical for this time of year, usually occurring in the first few weeks of October. && .LONG TERM /Thursday through Monday/... Issued 202 PM MDT MON OCT 12 2026 Warm, dry, and pleasant conditions will end the coming week as a Pacific ridge shifts to be over the Great Basin. This ridge will allow temperatures of 5-10 degrees above normal. Clear skies and good radiational cooling overnight will allow for a threat of mountain valley fog overnight into the mornings. A weak shortwave late Sunday will help lower temps a few degrees come Monday (although still leaning above normal). Flow aloft will become more zonal as a result, before becoming southwesterly Monday ahead of the next system. In the 7-10 day time frame, ensemble guidance is in good agreement on another trough digging down from the Gulf of Alaska. This will likely bring increasing chances of precipitation and cooler conditions by mid- week next week. && .AVIATION /00Z Tuesday through Wednesday/... Issued 550 PM MDT MON OCT 12 2026 Generally VFR. Scattered rain showers and low clouds will bring MVFR ceilings to the Magic Valley late this evening into the overnight. Patchy valley fog in Central ID Mountains bringing brief MVFR/IFR conditions. Mountains obscured in low clouds and precipitation with snow levels around 4500-5500 ft MSL. Widespread clearing tomorrow. Surface winds: W-NW 5-15 kt. Winds aloft at 10kft MSL: N-NE 10-20 kt becoming N 20-30 kt by Tues/12Z. KBOI...VFR. Skies clearing this evening/overnight, with mostly clear skies Tue/AM. Surface winds: NW 5-12 kt through the period. && .BOI WATCHES/WARNINGS/ADVISORIES... ID...Frost Advisory from midnight tonight to 10 AM MDT Wednesday for IDZ012-014-016. OR...Frost Advisory from midnight MDT /11 PM PDT/ tonight to 10 AM MDT /9 AM PDT/ Wednesday for ORZ064. && $$ www.weather.gov/Boise Interact with us via social media: www.facebook.com/NWSBoise www.x.com/NWSBoise AVIATION.....SA SHORT TERM...JDS LONG TERM....NF

334 FXUS65 KLKN 122050 AFDLKN Area Forecast Discussion National Weather Service Elko NV 150 PM PDT Mon Oct 12 2026 .KEY MESSAGES... * Most locations across northeastern and central Nevada are projected to receive an additional quarter inch to a half inch of rainfall by Tuesday afternoon. * Tonight into Tuesday morning snow levels lower to around 5000 feet across the region * Passes are expecting up to half an inch of snow and may see slick roads, while valleys will see a trace to half an inch mainly on grassy surfaces. * Dry Wednesday through Sunday. && .DISCUSSION... (This evening through next Sunday) WEATHER PATTERN OVERVIEW: Showers are continuing across Northeastern Nevada today and are expected to last through tomorrow afternoon. Snow is expected to mix in for the valleys by this evening, with snow levels dropping to around 5000 feet overnight. Any valley snow will be short lived, however a winter weather advisory is in effect for the Ruby Mountains and East Humboldt Range with 5 to 10 inches expected in the higher elevations. The low exits to the east on Tuesday, with showers clearing from west to east through the day and leaving dry conditions by nightfall. High temperatures will be in the 40s to mid 50s for Tuesday, warming into the 60s and 70s by Friday as a transient upper high enters the area. Lows will be unseasonably cool the next few nights, dropping to around 20 tonight and tomorrow night. Vulnerable plants and plumbing should be protected if they haven`t already been winterized. There are some early indications of another cold and wet system to start next week, but details are few and far between this far out. FORECAST CONFIDENCE & DEVIATIONS: High confidence in showers through Tuesday and in snow potential. Moderate confidence in dry and warming conditions after Tuesday. No changes were made to NBM output. && .AVIATION...Showers will continue to cause periods of degraded visibility and ceilings at KEKO/KENV/KELY through the next 24 hours. Snow may also mix in overnight as temperatures drop. Otherwise, winds will remain below 10KT, with the exception of two periods of gusts up to 25KT at KTPH. && .FIRE WEATHER...Dry conditions for zone 437. All other zones continue to experience scattered to numerous showers. Central Nevada has about a 15% chance of thunderstorms. Showers transition to mainly snow overnight as temperatures drop, then exit from west to east during the day Tuesday. Dry and mild for the remainder of the week. && .HYDROLOGY...While the flood watch was allowed to expire this morning, the threat for runoff and debris flows hasnt entirely ended quite yet. Light to moderate rainfall continues across much of the area today and may be enough to cause minor flooding in areas already saturated from recent rainfall. Showers will dissipate from west to east tomorrow. && .LKN Watches/Warnings/Advisories... Winter Weather Advisory from 5 PM this afternoon to 5 PM PDT Tuesday NVZ034. && $$ DISCUSSION...94 AVIATION...94 FIRE WEATHER...94 HYDRO...94