Area Forecast Discussion
Issued by NWS Spokane, WA
Issued by NWS Spokane, WA
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989 FXUS66 KOTX 030904 AFDOTX Area Forecast Discussion National Weather Service Spokane WA 104 AM PST Wed Dec 3 2025 .KEY MESSAGES... - Wintry mix Thursday evening into Friday may result in a slick commutes. - Warming temperatures and a transition of snow to rain late this week with breezy winds. - Moderate impacts from snow expected on the mountain passes late week into the weekend. && .SYNOPSIS... Quiet weather with low clouds and fog through Wednesday. Weather trends unsettled beginning Thursday. Temperatures may be cold enough Thursday night into Friday to support a lowland wintry mix. By Friday, temperatures will modify and warm above normal with unsettled weather continuing through the weekend and into next week. && .DISCUSSION... Today through tomorrow: The next couple days will have the forecast area see a break from precipitation. PWATs currently sit at 0.3- 0.5in, which is slightly lower (80-90%) of normal. The one exception will be in the mountains, where orographic lift could result in very light snow with no additional accumulations. The reason for this break is a strengthening ridge just off the PNW coast moving in bringing higher heights to the area. With stratus currently covering much of eastern Washington, fog formation will be difficult and patchy in nature. Western Okanogan County and Chelan County do not have stratus over them and currently have low visibilities, which are anticipated to continue through the morning. Tomorrow afternoon through Saturday: Tomorrow night through the weekend, an active weather pattern moves into the area off the coast. The aforementioned ridge will flatten, bringing a series of shortwaves across the area over the weekend. The air mass it will usher in will be warm and moist, with PWATs rising to 150-200% of normal (0.5-0.6in). The first wave of rain and snow will come through on Thursday night, but the bulk of precipitation associated with the event will fall Thursday into Friday afternoon. Mountain passes will see the heaviest snow. Probabilities of 6 inches of snow or more Friday through Saturday for mountain passes are: 25% for Stevens Pass, 45% for Lookout Pass, and 85% for Washington Pass. There is a chance for some lowland snow, but totals right now are hovering around an inch. Friday night, as anomalously warm temperatures are advected into the area, snow levels rise to 4000 feet through the weekend, leading to a transition from snow to rain for the lowlands. Main impacts from this series of weekend waves will be wintry conditions along mountain passes alongside lowland highway impacts during the snow to rain transition. With deterministic snow totals in the Cascades and Central Panhandle Mountains reaching 12 inches in the highest elevations, winter weather headlines will likely be needed for the weekend. This series of waves will, alongside the rain and snow, bring mild temperatures and gusty winds to the area as well. A surface low dropping into Montana will tighten the pressure gradient across Washington and Idaho, resulting in elevated wind gusts across the area. In particular, Wenatchee, Pullman, and Lewiston have a 25-35% chance of seeing wind gusts higher than 30 mph Friday night through Saturday morning. Winds will be elevated Thursday and Saturday night as well, but not as strong. Surface temperatures in the basin will rise to the mid-40s by Saturday, which is 6-8 degrees warmer than normal for this time of year. Sunday through Wednesday: The active weather pattern continues through the end of the weekend and into next week. Another series of shortwaves move through, with early signals showing even warmer temperatures and higher PWATs than this weekend. The Extreme Forecast Index in particular highlights much warmer temperatures than normal next Tuesday alongside stronger gusts throughout the area. PWATs in long range ensembles rise to nearly 200-250% of normal (0.7-0.8in). Early precipitation estimates show higher snow totals. Current cluster analysis shows 80% agreement on higher than normal heights early next week. The Climate Prediction Center`s 6-10 day outlooks show a 70-90% chance of above average temperatures and a 50-70% chance for above normal precipitation. Should models continue showing such trends over the next few days, this will be a system to monitor very closely. /AS && .AVIATION... 06Z TAFs: While models initially began this TAF period with IFR/LIFR conditions for many TAF sites, all sites but KEAT/KPUW are at VFR/MVFR currently. This is due to stratus that has moved in, which may make fog formation difficult. Ceilings and visibilities are still projected to drop within a few hours, but may not get as low as some models, particularly the NBM, are thinking. KSFF/KCOE/KPUW/KLWS/KMWH all have roughly a 20 percent chance of IFR conditions throughout the TAF period. For KGEG, model guidance is particularly pessimistic about ceilings, with a 60% chance of LIFR conditions through around 15Z. KPUW/KLWS have conditions improving by the end of the TAF period, while all other sites will end the TAF period at either IFR or LIFR. Probabilities for precipitation lie at 30 percent and below for all locations. .FORECAST CONFIDENCE AND/OR ALTERNATE SCENARIOS: High confidence in precipitation chances being low throughout the forecast period. High chances in continued degraded ceilings for KEAT/KPUW. Moderate confidence in fog formation elsewhere due to a stratus deck that has moved in. /AS ----------------------- 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 36 29 34 30 39 34 / 10 10 60 50 90 40 Coeur d`Alene 38 30 35 31 39 35 / 20 30 70 50 90 70 Pullman 38 27 35 32 43 36 / 10 10 80 70 100 80 Lewiston 42 31 40 36 47 41 / 0 10 70 70 90 80 Colville 37 24 36 24 37 25 / 10 20 50 40 90 40 Sandpoint 35 28 35 29 36 33 / 30 40 80 60 100 80 Kellogg 38 32 35 33 41 37 / 30 40 90 70 100 90 Moses Lake 38 29 36 29 44 32 / 10 10 40 30 60 20 Wenatchee 41 30 39 33 47 38 / 10 10 30 40 80 50 Omak 39 28 37 29 38 30 / 0 10 30 30 70 30 && .OTX WATCHES/WARNINGS/ADVISORIES... WA...None. ID...None. && $$