Area Forecast Discussion
Issued by NWS Spokane, WA
Issued by NWS Spokane, WA
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011 FXUS66 KOTX 262306 AFDOTX Area Forecast Discussion National Weather Service Spokane WA 306 PM PST Wed Nov 26 2025 .KEY MESSAGES... - Snow impacting travel in the East Slopes and along Hwy 20 tonight through Thanksgiving then Lookout Pass Thursday night into Friday morning. - Colder temperatures over weekend into next week with occasional chances for snow showers. && .SYNOPSIS... Precipitation moves in Wednesday night through Thanksgiving. A mix of rain and snow is expected for the northern mountain valleys and additional light snow over mountain passes resulting in minor impacts to travel. A dry, cold air push will bring colder temperatures for the weekend. && .DISCUSSION... Tonight through Friday: A potent low pressure system is tracking across the Eastern Pacific toward the WA Coast and is expected to make landfall Thursday afternoon. The system will deliver additional rounds of precipitation to the region coming in the form of rain and snow. Where snow falls will be a bit more complex vs the Tuesday-Wednesday morning system. A weak midlevel warm front will lift south to north over the region overnight bringing the first round of light precipitation. Many lowlands across the northern mountains and East Slopes were socked in low clouds today. This kept temperatures varying from 32-35F vs the upper 30s and lower 40s. Models suggest midlevel temperatures for areas along and north of Hwy 20 and within the upper river valleys of the East Slopes including Leavenworth, Winthrop, Republic, Ione, and Bonners Ferry are expected to remain near 0C or colder. As such, the forecast has been adjusted to lower snow levels and maintain snow as the p-type though accumulations with the first wave of moisture will likely be low with snow falling with temperatures near or just above freezing and weak ascent through the dendritic layer. Heavier precipitation will arrive through the day on Thursday as the low nears the coast and pushes a cold occluding front inland. Forcing ahead and along the occluded front will ramp up, especially through the dendritic layer while easterly winds dam cooler air into the E Slopes. This combination will work against rising snow levels blasting northward north of the International border and it conceivable that upper reaches of the Methow Valley, Republic Area, Upper Pend Oreille River Valley, and Porthill/Bonners Ferry area experience multiple hours of snow from late tonight into Thursday night. Intensities will vary over time which will limit accum due to temperatures wavering from 32-35F; would not rule out 1-3 inches for these lowlands with local amounts in excess of 5 inches on the higher benches and peaks including Washington, Loup Loup, and Sherman Passes and this is reflected in the latest forecast. If you are traveling over these passes, please be prepared for snowy travel. The warmer air will have an easier time working into the Cascade passes for Hwy 2 and I-90 where temperatures are already near 33F and not expected to cool. Snow is in the forecast for tonight but a transition to rain is expected with light slushy, accumulations. Lookout Pass is also near 33F with wet snow expected with the warm front but minor impacts are expected as snow levels will have ample time to rise before the heavier precipitation arrives Thursday afternoon. For the remainder of the lowlands, weather impacts will come in the form of patchy dense fog and light to moderate rains. The remnants of the low pressure system will track through the Inland NW Thursday night into Friday morning and depart to the southeast. Gusty northerly winds will be drawn into the departing system with speeds magnified down the Okanogan Valley where gusts will be on the order of 20-30 mph. These northerly winds will draw cooler air back into the region with snow levels falling over the lower Idaho Panhandle and Blue Mountains and periods of moderate snow in the mountains. Greatest impacts to Lookout Pass will come Thursday night into Friday morning where 4-6 inches of snow is expected to fall. The higher benches of the Camas Prairie will also see a transition to wet snow with potential for an inch. The remainder of the region will dry out with clear skies. The increased winds will also deliver increased probabilities to scour out low clouds and fog. Saturday-Sunday: A ridge of high pressure will amplify over the E Pacific placing the INW under northwest flow aloft. There is good agreement of another shortwave dropping down from the northwest on Saturday, generally quick hitter, fashion. This will bring a renewed threat for snow showers to the Cascades and anywhere from a trace to two inches. The flow pattern would also favor the rising terrain of the Camas Prairie and Blue Mountains for a quick tenth of QPF and light snow accumulations above 2500 feet. Breezy north to northeast winds will continue to draw cooler continental air in from the north and east. Monday-Thursday: There is good agreement amongst the ensembles for the upper-level ridge to waver around over the Eastern Pacific and at times, flop over into the coastal Pac NW. This will result in near to below normal temperatures for the Inland NW through the period with occasional chances for weaker waves to drop in from the northwest bringing rain and snow showers. When these waves are not present, there are increased odds for dry and chilly conditions and periods of afternoon sunshine. /sb && .AVIATION... 18Z TAFs: An extremely moist boundary layer coupled with warming midlevels over light lowland snow will result in high probabilities for low ceilings (LIFR/IFR) conditions from KCOE- KGEG with low confidence in exact details with the forecast through 06z. A deepening low off the WA Coast will result in increasing easterly winds which leads to higher confidence for KPUW and KLWS to see improvements though on the contrary, this will lead to lowering cigs for KEAT and areas across the Basin including KMWH will be in the cross-hairs with moderate confidence for periodic improvement. A warm front lifts through 06-10z delivering another band of light rain to the lowlands snow in the mountains. The period of rain comes with low to moderate confidence to briefly break up the low clouds but as the rain departs to the north, cigs are likely to lower again. /sb .FORECAST CONFIDENCE AND/OR ALTERNATE SCENARIOS: There is moderate confidence in MVFR to LIFR through the TAF period for all sites except for KLWS. For KPUW, there is moderate to high confidence for rising cigs (HREF has 100% chance to rise above 1000 feet) and maintain 6SM or higher due to persistent easterly winds. KMWH comes with lower confidence and only 70% for cigs above 1000 feet. Biggest uncertainty will impacts on vis and cigs with rain overnight and how quickly conditions deteriorate in the wake of the rain. ----------------------- 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 35 41 35 42 25 36 / 40 90 90 40 0 10 Coeur d`Alene 35 41 35 40 24 35 / 50 90 100 70 10 10 Pullman 36 44 36 40 27 38 / 50 60 100 90 20 20 Lewiston 39 49 40 46 32 41 / 40 30 90 80 10 10 Colville 27 39 28 42 21 37 / 40 100 90 20 0 10 Sandpoint 31 39 31 39 21 32 / 50 100 100 80 10 10 Kellogg 37 44 36 39 23 35 / 60 90 100 90 20 20 Moses Lake 37 43 35 46 28 40 / 40 90 70 20 0 20 Wenatchee 36 41 37 45 32 38 / 70 90 80 10 0 20 Omak 33 39 32 43 27 37 / 50 90 60 0 0 10 && .OTX WATCHES/WARNINGS/ADVISORIES... WA...None. ID...None. && $$