


Area Forecast Discussion
Issued by NWS Spokane, WA
Issued by NWS Spokane, WA
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080 FXUS66 KOTX 280759 AFDOTX Area Forecast Discussion National Weather Service Spokane WA 1259 AM PDT Thu Aug 28 2025 .KEY MESSAGES... - Scattered showers with isolated thunderstorms through Thursday. Thunderstorms will be capable of heavy rainfall. - Warming up into the 90s next week, locally near 100, with elevated HeatRisk. && .SYNOPSIS... An area of low pressure will bring scattered showers and isolated thunderstorms to the Inland Northwest through Thursday. Thunderstorms will bring the potential for heavy rainfall particularly in the Cascades and in the Idaho Panhandle. Limited shower chances linger Friday and then brush by the Cascades later in the weekend. Otherwise drier weather returns, with temperature warming into next week. && .DISCUSSION... Today and tonight: a moisture-rich low pressure system migrates north through this period. Precipitation chances will be found along the deformation axis over a good chunk of the area this morning, the potential shifts toward the north and around the Cascades this afternoon and evening. Some embedded t-storms will be possible, particularly near the Cascades and closer to northeast WA and ID Panhandle mountains. There is about 20-30% chance in these areas. Destabilization on the south side of the deformation axis will also allow for the additional shower and isolated t-storm chances to develop around the Columbia Basin and higher Palouse. Most of the deeper moisture (PWATS around 180-229% of normal) is above 10000 feet so that will limited precipitation amounts, especially away from the mountains. However the system will has the potential for some wetting rains. The best chance outside the mountains will be earlier today before the boundary lifts north. The chance of wetting rain (>=0.10") in these areas is around 10-30%, with the higher risk toward he WA/ID border. Closer the the mountains both this morning through this evening the potential for wetting rains is around 20-40%, locally between 60-80% around the Cascades and central Panhandle mountains early today. Given the burn scars in the region, a flood watch is in place for the Cascades through this evening. As we head into late this evening into the overnight the primary shower chance retreat to the northern mountains and wane. Given the moisture we will be on the look out for some patchy fog late tonight into Friday morning over the eastern third of WA and ID, particularly around the sheltered valleys and near bodies of water. Friday a boundary lingers around the north to northeast CWA, with some modest PWATs still in place at 120-160% of normal. The afternoon also brings modest instability. This will bring renew the threat of showers and thunderstorms over the northern WA mountains and north and central ID Panhandle. These could be locally stronger with heavy downpours and gusty winds, maybe some hail. Something to keep an eye on is the potential for some of this activity outside the mountains, over the north and eastern basin (including the Spokane area). However ensembles and CAM models are holding PoPs at around 10% or less in these areas. Definitely worth monitoring but confidence is too low to include in the forecast. Saturday to Wednesday: models bring a deep low pressure trough toward the region and then retrograde it back into the Pacific heading into early next week. Models have been pretty inconsistent over the past several days in what to do with that low. So this retrograde west and away from the area into next week has medium confidence. Overall the low brushes the western side of the state Saturday into Sunday, bring some shower chances to the Cascades Saturday night into Sunday. Thereafter the area dries out and begins to warm up heading into the new work week. Ensembles show about about 70-90% chance of pushing into the 90s and and about a 40-60% chance of reaching near 100 over the deeper basin heading into Tuesday and Wednesday of next week. HeaRisk rises toward the elevated range again. Summer is not over. /Solveig && .AVIATION... 06Z TAFS: An area of light rain will continue to impact areas from the Cascades to Idaho tonight into Thursday morning. Some steadier rain is possible at times and locally deeper moisture will carry a risk for some MVFR ceilings near PUW/LWS. Elsewhere look for VFR conditions. The threat of rain lifts northward Thursday afternoon, but some pop-up showers or isolated t-storms are possible in the afternoon before drying out from the south in the evening. FORECAST CONFIDENCE AND/OR ALTERNATE SCENARIOS: High confidence in continued VFR conditions at most TAF sites. HREF model indicates a 30 percent chance for ceilings lowering down to around 3,000 ft agl near KLWS/KPUW. Low confidence for thunderstorms impacting airport terminals. ----------------------- 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:/weather.gov/otx/avndashboard && .Preliminary Point Temps/PoPs... Spokane 81 58 88 59 92 60 / 40 10 10 0 0 0 Coeur d`Alene 79 60 86 59 91 61 / 40 20 10 10 0 0 Pullman 80 53 87 54 89 55 / 40 10 0 0 0 0 Lewiston 87 64 93 64 96 66 / 30 0 0 0 0 0 Colville 84 51 88 49 91 51 / 20 30 20 10 0 0 Sandpoint 79 55 84 54 89 55 / 30 30 30 10 0 0 Kellogg 74 60 83 61 88 63 / 60 30 30 10 0 0 Moses Lake 88 60 92 60 95 62 / 30 10 0 0 0 10 Wenatchee 87 67 92 68 93 68 / 50 20 10 0 10 20 Omak 86 63 91 63 93 64 / 50 20 20 10 0 10 && .OTX WATCHES/WARNINGS/ADVISORIES... WA...Flood Watch from 11 AM PDT this morning through this evening for Central Chelan County-Okanogan Highlands-Okanogan Valley-Wenatchee Area-Western Chelan County-Western Okanogan County. ID...Air Quality Alert until 11 AM PDT this morning for Central Panhandle Mountains-Idaho Palouse-Lewis and Southern Nez Perce Counties-Lewiston Area. && $$