Area Forecast Discussion
Issued by NWS Spokane, WA
Issued by NWS Spokane, WA
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738 FXUS66 KOTX 230608 AFDOTX Area Forecast Discussion National Weather Service Spokane WA 1008 PM PST Sat Nov 22 2025 .KEY MESSAGES... - Light snow returns to the mountain passes Sunday evening and night. - Gusty winds with a cold front passage Sunday night through Monday. - Valley snow potential Tuesday night into Wednesday. Moderate snow on the mountain passes. && .SYNOPSIS... The weather will remain quiet through Sunday with near to warmer than normal temperatures. A low pressure system will move in at the end of the weekend. Snow will impact the mountain passes beginning Sunday evening and again Tuesday night into Wednesday. This midweek system will bring the potential for light snow in the lowlands and moderate to heavy snow over the mountains. Mainly light mountain showers on Thursday. && .DISCUSSION... Saturday and Sunday: A weak ridge of high pressure is bringing fairly mild and mostly dry conditions to the INW today ahead of an incoming cold front. Temperatures will peak in the 40s to low 50s today with the coolest temperatures in central WA. A stubborn low stratus deck has led to slower than anticipated warming in central Washington. Not often is Spokane 10 degrees warmer than Moses Lake. A weak atmospheric river currently impacting Vancouver Island is starting to sag south this afternoon bringing increased cloud cover and chances for snow showers in the Cascades/northern mountains above 6000`. Rain chances increase in the lowlands late tonight and into Sunday morning as synoptic forcing improves thanks to an approaching cold front. With snow levels around 4500-5500 feet, snow impacts will be minimal. Models have slowed the progression of the the mid-level shortwave trough, which would hamper the potential of a convergence zone establishing in western WA. Low level flow is favorable but lapse rates do not steepen until the shortwave passes through Sunday night. Snow amounts look fairly light for Stevens Pass (2-4") and Washington Pass (3-5"). Rain amounts in the lowlands through Sunday night will be very light (0.01-0.05") in central WA but a bit higher in eastern WA and north ID (0.10-0.25"). Southwest winds will increase in the lowlands of eastern WA and north Idaho as the front passes and cold advection through Monday morning with sustained speeds around 10-20 mph gusting up to 35 mph on the Palouse. Monday and Tuesday: Southwest winds will continue through the early afternoon but slowly subside in the evening hours as the shortwave trough departs. Light precipitation will continue in the Cascades and Idaho Panhandle mountains with strong west/northwest flow aloft. The lowlands will be dry with highs in the 40s. Monday will be a good travel day. Monday night will be cold with lows in the low 20s to low 30s as drier air and fairly minimal cloud cover initially will allow for strong radiational cooling. It would be even cooler if a cirrus deck was not moving into the region early Tuesday morning. Much of Tuesday will be a good day for travel ahead of incoming weather system under the influence of a weak ridge of high pressure. Tuesday night into Wednesday: The upper air pattern still indicates a mid-level ridge but changes will rapidly occur thanks to a deepening low pressure system off the coast. What we know: A warm front will surge through the region some time between Tuesday night and Wednesday morning which will bring a round of moderate precipitation to the region. What is more uncertain are the snow levels with this system and the timing of the precipitation. Details will be ironed out as the event comes closer. There is moderate confidence for the antecedent air mass to be cold enough to support lowland snow at the onset on the event. There is also moderate confidence for the colder air to remain more stubborn in the E Slopes of the Cascades and near the immediate Canadian border. The details are muddy still but with Wednesday being a very busy travel day, this forecast should be watched closely, especially since the lowlands have not experienced a snow event in a while. Outside of the lower Columbia Basin there is a 15-30% chance of at least an inch of snow during this period. Mountain pass chances of 6+" 4 PM TUE - 4 PM WED: Stevens: 45% Washington: 40% Snoqualmie: 25% 6+" chance 4 PM WED - 4 PM THU further east: Lookout: 20% Thursday onward: By Thursday, snow levels will raise to above 5000`, minimizing impacts to the mountain passes. Ensemble clusters are indicating the potential for another wave which would bring additional precip to the region late next week but confidence is very low. /DB && .AVIATION... 06Z TAFs: A front edging into the area will bring an increased chance of light rain overnight into Sunday morning. Low level moisture is forecast to bring EAT/MWH MVFR/IFR conditions much of the period. Limited rain chances will be found here. VFR condition start at GEG/SFF/COE/PUW/LWS, then conditions start to deteriorate toward MVFR later overnight into Sunday with some increased rain chances, becoming more likely toward later Sunday. .FORECAST CONFIDENCE AND/OR ALTERNATE SCENARIOS: Moderate confidence in timing of VFR transitioning to MVFR conditions. Low to moderate confidence in precipitation timing. Patchy fog and localized reductions in visibility are expected around the Columbia Basin. Low confidence chance for LIFR visibility near MWH due to this risk tonight into early Sunday. ----------------------- 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 37 46 32 43 25 39 / 20 60 70 10 0 10 Coeur d`Alene 38 46 34 42 27 39 / 20 70 90 30 10 10 Pullman 36 48 32 41 25 39 / 10 40 90 30 10 10 Lewiston 39 51 38 47 30 43 / 0 20 80 10 10 10 Colville 32 44 28 44 21 39 / 40 80 70 10 0 20 Sandpoint 36 43 33 41 25 37 / 50 90 100 50 20 20 Kellogg 39 47 34 40 28 39 / 10 70 100 60 30 30 Moses Lake 34 47 29 48 23 40 / 10 30 20 0 0 20 Wenatchee 39 48 33 46 30 40 / 20 50 20 0 0 30 Omak 37 45 31 45 27 39 / 20 40 20 0 0 10 && .OTX WATCHES/WARNINGS/ADVISORIES... WA...None. ID...None. && $$