Area Forecast Discussion
Issued by NWS Spokane, WA
Issued by NWS Spokane, WA
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386 FXUS66 KOTX 302201 AFDOTX Area Forecast Discussion National Weather Service Spokane WA 201 PM PST Sun Nov 30 2025 .KEY MESSAGES... - Light snow late Monday into Tuesday, especially in the Central Panhandle Mountains. - Modifying temperatures and a transition of snow to rain late this week. && .SYNOPSIS... A weather system on late Monday into Tuesday will bring light snow mainly to the Idaho Panhandle and extreme Eastern Washington. Temperatures will modify and warm above normal late this week. Unsettled late this week as well with snow transitioning to rain in the lowlands. && .DISCUSSION... Tonight: A short wave ridge off the coast will move over the region tonight for dry conditions. An abundance of stratus today over Southeast Washington into the south ID Panhandle has been slowly moving north this afternoon as boundary layer winds shift out of the south. Continued expansion of stratus northward is expected through tonight, which should help keep fog coverage mostly patchy in coverage. Monday through Tuesday: A wave topping the ridge moves over the region bringing an increased threat of mainly snow Monday afternoon into Tuesday as colder temperatures support low snow levels. Precipitable water values briefly increase to around 150-175% of normal, which combined with isentropic ascent into the ID Panhandle and eastern third of Washington leads to the development of light snow. The highest amounts are expected in the Central Panhandle Mountains and the Camas Prairie where upslope flow is maximized. The 12z ECMWF ensembles have trended upward with precipitation totals and snow amounts. Here are the latest NBM chances for 1" of snow or more: Colville: 20%, Spokane 15%, Pullman 20%, Sandpoint 60%, Kellogg 60%. Given that the latest NBM doesn`t have the 12z ECMWF ensembles incorporated, it`s possible that these numbers increase with the next run. Tuesday Night and Wednesday: As this system pushes east, a short wave ridge moves in for another drier period. A moist boundary layer combined with the ridge is a good setup for more fog and stratus over the region. Thursday through Sunday: An active pattern becomes established by the weekend as an arctic air mass slides south into Central British Columbia, while a strong pacific jet also takes aim at the region. The jet is likely to keep cold air well north of our area, with 85% of the ensembles favoring an active jet over the region with an influx of moisture and milder air. The increase in temperatures and snow levels will result in mainly a valley rain and mountain snow situation although some valleys may begin as snow with the inital warm front late Thursday or Friday before snow levels rise. The strong jet will also bring breezy to windy conditions on Friday. There is some model spread in the details that far out regarding exactly how windy. The NBM currently has a 30% chance of wind gusts exceeding 40 MPH at Wenatchee and Pullman, and a 15% chance for Spokane. Wenatchee has a 20% of gusts exceeding 50 MPH as well. Similar probabilities are forecast for Saturday and Sunday. JW && .AVIATION... 18Z TAFs: Low clouds have become established across southeast Washington and the lower Idaho Panhandle as well as around Bonners Ferry, ID. IFR to LIFR conditions look to persist at KPUW into Sunday afternoon. As these clouds break, there is a moderate chance for fog or low stratus to redevelop after sunset. KLWS is also experiencing ceilings between 1-2 kft and will see gradual lifting Sunday evening. Patchy fog will be present in the mountain valleys of the east slopes of the Cascades and northern mountains of Eastern Washington and north Idaho mainly near water bodies. Boundary layer winds will be shifting from NE to S/SW today with moderate confidence for the bank of low clouds around KPUW to advect northward into KGEG/KSFF/KCOE. Exact timing and how quickly conditions transition from VFR to MVFR/IFR comes with low confidence. .FORECAST CONFIDENCE AND/OR ALTERNATE SCENARIOS: For timing of low clouds reaching KGEG-KCOE, there is low confidence. Based on satellite trends quicker timing is preferred. Confidence low for restrictions impacting KEAT/KMWH outside very shallow, patchy fog. JW ----------------------- 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 25 32 28 34 24 36 / 0 20 40 20 0 0 Coeur d`Alene 25 33 29 35 27 38 / 0 20 60 40 0 0 Pullman 24 36 29 35 28 38 / 0 20 50 70 10 0 Lewiston 28 38 33 41 33 42 / 0 10 40 60 10 0 Colville 19 32 22 37 19 37 / 0 40 40 10 0 0 Sandpoint 22 32 27 34 25 35 / 10 50 80 40 10 10 Kellogg 25 33 32 35 29 38 / 0 30 70 80 10 10 Moses Lake 24 36 27 38 24 38 / 0 10 20 0 0 0 Wenatchee 29 35 32 39 30 41 / 0 10 20 0 0 0 Omak 25 35 27 39 27 39 / 0 20 20 0 0 0 && .OTX WATCHES/WARNINGS/ADVISORIES... WA...None. ID...None. && $$