238 FXUS66 KOTX 281245 AFDOTX Area Forecast Discussion National Weather Service Spokane WA 545 AM PDT Mon Jul 28 2025 .KEY MESSAGES... - Temperatures warming into the 90s to 100s next week with widespread Moderate and localized Major HeatRisk Tuesday and Wednesday. - 10-20 percent chance of thunderstorms Wednesday then 20-40 percent chance Thursday. 10-30 percent chance lingers over the northern mountains and ID Panhandle Friday. && .SYNOPSIS... Temperatures will trend warmer through the early week with highs in 90s and low 100s for Tuesday and Wednesday. There are increasing chances for afternoon and evening thunderstorms by the middle to end of next week. && .DISCUSSION... Morning update sent earlier to include thunderstorms for SE WA and the lower Idaho Panhandle. Well defined midlevel circulation and unstable environment has been very effective at high based thunderstorms with scattered lightning strikes and possibly some small hail. Monday through Wednesday: A ridge beginning to build in western Canada will promote a warming trend through much of the work week. Temperatures will be at their hottest on Tuesday and Wednesday, with high 90s to low 100s anticipated throughout much of the area. Low temperatures these nights will be in the mid 60s, which could create some problems for people prone to heat-related illnesses without adequate cooling. Widespread moderate to local major HeatRisk is anticipated. This ridge strengthening will also provide a transition from southwesterly flow to southerly flow. As this southerly flow brings in warmer, moister air, thunderstorm potential increases. The GFE has surface-based CAPE values rising to 200-500 J/kg for these days. Thunderstorm coverage is limited to far southeastern and northeastern Washington, and the northern Idaho Panhandle, where NBM probabilities show a 5-10 percent chance of thunder on these evenings. Wednesday evening through Sunday: Lower heights and moisture forming over California will result in a more robust surge of warmth and moisture Wednesday through Friday. Additionally, on Thursday, as heights down in the southwest lower further, a shortwave will move through the area, providing a boost in lift as well. As of right now, NBM thunder probabilities increase from 5-10 percent on Tuesday to 10 to 15 on Wednesday, and further to 15 to 25 percent on Thursday and Friday afternoon. Thunderstorm coverage also increases, with much of the forecast area showing chances for thunder. Surface- based CAPE also jumps from 200-500 J/kg on Wednesday to 500-1000 J/kg on Thursday and Friday, with localized areas of 1000-1500 J/kg in northeastern Washington and in the northern Idaho Panhandle. This will create a very favorable environment for thunderstorms, and with long range models such as the ECMWF and GFS ensembles showing PWATS near 150 percent of normal on Thursday night, indicates these will be wet thunderstorms. With wet thunderstorms comes higher chances of heavy rainfall rates within cores in addition to lightning and strong outflow wind gusts. This could result in potential flood issues, particularly within burn scars. With medium-range models favoring thunderstorm chances, a very close eye will be kept on this event as it nears, particularly as short-range CAMs become available. /AS && .AVIATION... 12Z TAFS: Through 17z, main concern will be cluster of thunderstorms tracking NE across the lower Idaho Panhandle. Currently between LWS-PUW and will be tracking toward MLP around 15-16z. There are cumulus buildups starting around Spokane-Cd`A as well. Would not rule out a few cells maturing into showers or even a brief t-storm. This comes with low confidence but given the instability noted on the 06z balloon data, it would not take much. Otherwise, VFR conditions will prevail with some high clouds moving across the region. Winds will be light today with infrequent afternoon gusts of 15 mph. After 22z, focus will shift toward a renewed threat for thunderstorms between NE Oregon and W Montana with 10-20% chance to skirt Lewiston 01-03z. FORECAST CONFIDENCE AND/OR ALTERNATE SCENARIOS: High confidence in VFR conditions for majority of the region. Low confidence in afternoon thunderstorms impacting LWS after 00z. /sb && .Preliminary Point Temps/PoPs... Spokane 91 61 95 63 96 65 / 0 0 0 0 0 10 Coeur d`Alene 91 60 94 64 95 64 / 10 0 0 10 0 20 Pullman 88 58 93 60 93 60 / 20 10 0 10 10 20 Lewiston 95 68 101 69 100 69 / 20 10 0 10 10 10 Colville 90 51 95 55 96 55 / 0 0 0 0 10 10 Sandpoint 87 55 92 59 91 60 / 10 0 0 10 10 20 Kellogg 88 63 93 67 92 67 / 20 0 0 10 10 20 Moses Lake 94 60 99 64 100 66 / 0 0 0 0 0 10 Wenatchee 93 68 98 72 99 74 / 0 0 0 0 0 10 Omak 93 63 99 65 100 66 / 0 0 0 0 10 10 && .OTX WATCHES/WARNINGS/ADVISORIES... WA...None. ID...None. && $$