Area Forecast Discussion
Issued by NWS Boise, ID
Issued by NWS Boise, ID
669 FXUS65 KBOI 112120 AFDBOI Area Forecast Discussion National Weather Service Boise ID 220 PM MST Tue Nov 11 2025 .SHORT TERM...Tonight through Thursday night...No major change from previous forecast, with mild, dry weather continuing through Thursday morning due to an upper ridge over the interior western US. The ridge will maintain a weak inversion in the valleys. On Thursday the ridge will shift eastward and clouds will increase in OR under moistening southwest flow aloft. Light rain will begin in Harney and Baker Counties Thursday morning, then spread eastward into ID later Thursday and especially Thursday evening, as a Pacific cold front moves through. Latest adjustments have Thursday 1 to 3 degrees cooler than Wednesday in Oregon, but 1 to 3 degrees warmer than Wednesday in Idaho. Thursday night should be mild everywhere due to clouds and pcpn. Pcpn timing looks about the same as before, but amounts and PoPs have been lowered slightly. The Boise Mountains and West Central Idaho Mountains still look like the wettest areas with generally .25 to .60 inch total pcpn Thursday afternoon through Friday night, including 1 to 3 inches of snow as the snow level drops below 6000 feet Friday morning. The rest of our CWA should have less than .25 inch, most of that in the mountains, with less than .10 inch of rain in the valleys. Winds will continue light east or southeast through Thursday, then light west or northwest Thursday night behind the cold front. .LONG TERM...Friday through Tuesday...Unsettled conditions will prevail throughout the period. Precipitation will continue Friday morning, primarily across SW-Idaho, as the upper level trough and cold front continue to move across our area. Chances of precipitation Friday morning will range from 30-50% across lower elevations, and 60-90% in the west Central Mountains. Following the cold front, snow levels will drop to 5-6 kft MSL. In general, locations above 5500 ft MSL will see a 30-70% chance of receiving at least four inches of snow Friday/Saturday (increasing with elevation). The current forecast package has snow totals of 2-6 inches across high mountain passes and ridgelines. Through Saturday, the trough that brought us our late week weather will set up off of the coast of SoCal as a cut-off low. This will allow brief ridging to build in late Saturday/early Sunday. The lull in activity will be short- lived though. There is a strong signal of another system making its way across our area early next week. All major ensembles (and thus, the grand ensemble) show troughing making its way in from the Pacific; however, the depth of this system and the specific timing leave much to be resolved. Either way, this will result in elevated precipitation chances Sunday afternoon through Tuesday. Temperatures will cool to a around 5 degrees above normal on Tuesday, gradually lowering each day to near normal by Monday. && .AVIATION...VFR under increasing mid/high-level clouds. Surface Winds: Variable up to 10 kt. Winds aloft at 10kft MSL: W 10-20 kt. KBOI...VFR. light and variable this afternoon, becoming SE up to 6 kt after sunset. && .AIR STAGNATION...Weak surface-based inversion will continue through early Thursday as high pressure aloft and subsidence keep mixing heights near 2 kft AGL in the valleys. Mixing will increase and deepen later Thursday, and especially Thursday night as a Pacific surface cold front moves through, ending the inversion and improving circulation. && .BOI WATCHES/WARNINGS/ADVISORIES... ID...None. OR...None. && $$ www.weather.gov/Boise Interact with us via social media: www.facebook.com/NWSBoise www.x.com/NWSBoise SHORT TERM...LC LONG TERM....NF AVIATION.....NF AIR STAGNATION...LC