Area Forecast Discussion
Issued by NWS Spokane, WA
Issued by NWS Spokane, WA
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927 FXUS66 KOTX 180549 AFDOTX Area Forecast Discussion National Weather Service Spokane WA 949 PM PST Mon Nov 17 2025 .KEY MESSAGES... - Light snow over Washington Pass and Stevens Pass Monday night. - Temperatures trending cooler this week. && .SYNOPSIS... Next round of precipitation arrives Monday night into Tuesday morning. Mild temperatures will keep snow levels high with primarily light rain expected. Temperatures cooling closer to normal for the latter half of next week. Forecast has trended drier for the end of the week into the beginning of the weekend, but there still exists a 5-10% chance for moderate snow over Stevens and Washington Pass on Saturday. && .DISCUSSION... Monday night and Tuesday: An upper-level low, currently centered over southern Vancouver Island/northwest Washington, will track across northeastern Washington this evening. This system will be the primary driver for the next round of precipitation. The highest probabilities (greater than 80%) for precipitation are focused across the north Cascades, northeast WA, and the ID Panhandle this evening and overnight, with chances diminishing further south. Lingering precipitation chances (30-50%) will persist over northeast WA and the ID Panhandle through Tuesday afternoon. The primary forecast challenge is exact precipitation amounts, which will be dependent on the lows exact track. Ensemble guidance highlights this uncertainty: members tracking the lows center near the US/Canadian border produce lower precipitation amounts, whereas a more southern track through eastern Washington yields higher totals. Snow levels over the Cascades, currently near 6000 feet, will fall to approximately 3000 feet overnight. This will transition pass- level precipitation from rain to snow. Accumulations are track- dependent, with the NBM indicating the greatest potential over Washington Pass (40% chance of 4 inches, 25% chance of 6 inches). Probabilities for Stevens Pass are lower (20% chance of 4 inches, 10% chance of 6 inches). Travelers over the passes tonight should be prepared for winter driving conditions, though accumulations are expected to remain below advisory criteria. Cool air behind the low will result in Tuesdays highs being 5-10 degrees cooler than Monday, with most locations in the 40s. A building upper ridge and drier air mass Tuesday night will promote efficient radiational cooling, leading to high confidence in widespread freezing temperatures Wednesday morning. Fog development in sheltered valleys may mitigate the lowest temperatures in those specific areas. Wednesday through Sunday: Model consensus is high for a transient upper-level ridge to build over the region, providing dry conditions on Wednesday. Uncertainty increases significantly for the Thursday- Sunday period as models show another upper- level low digging in the eastern Pacific and closing off as it moves toward California. Recent ensemble guidance has trended drier for the Inland Northwest, suggesting a split flow pattern over the western US and subtle ridging over the region. This is a significant change from guidance 24 hours ago, which had indicated potential for a moderate snow event in the Cascades. Given the poor run- to-run model consistency, precipitation chances will be maintained in the forecast from Thursday onward until a clearer solution emerges. /vmt && .AVIATION... 06Z TAFs: IFR/MVFR conditions will continue across the region through Tuesday morning over GEG/SFF/COE as an area of low pressure tracks in. Some -ra will also impact between about 06-10Z. Other TAF sites will vary between MVFR/VFR, with VFR conditions more likely near EAT and MWH. A secondary wave passes over the area Tuesday afternoon to evening, with more clouds and an improvement to VFR conditions is forecast toward 18-21Z at all TAF sites. The threat of precipitation with this secondary wave will be very limited. Heading into Tuesday evening the threat of MVFR returns over GEG/SFF/COE. .FORECAST CONFIDENCE AND/OR ALTERNATE SCENARIOS: High confidence of IFR/MVFR conditions for GEG/SFF/COE. Moderate confidence is MVFR at PUW/LWS. Moderate to high confidence in VFR conditions at MWH/EAT. High confidence for VFR conditions Tuesday afternoon for all TAF sites. ----------------------- 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 44 31 45 30 46 / 70 40 10 0 10 10 Coeur d`Alene 39 45 32 45 32 46 / 80 60 30 10 10 20 Pullman 36 44 29 46 32 47 / 50 40 20 10 10 20 Lewiston 44 50 34 49 35 50 / 40 30 20 0 10 10 Colville 33 47 28 46 26 46 / 90 70 30 10 10 20 Sandpoint 38 45 32 44 30 44 / 90 90 50 20 10 30 Kellogg 40 45 32 46 34 49 / 80 80 50 20 10 30 Moses Lake 34 48 29 47 31 48 / 40 10 0 0 10 10 Wenatchee 37 48 33 46 35 48 / 60 20 0 0 20 10 Omak 39 47 32 45 33 46 / 80 40 10 0 10 10 && .OTX WATCHES/WARNINGS/ADVISORIES... WA...None. ID...None. && $$