Area Forecast Discussion
Issued by NWS Boise, ID
Issued by NWS Boise, ID
142 FXUS65 KBOI 122119 AFDBOI Area Forecast Discussion National Weather Service Boise ID 219 PM MST Wed Nov 12 2025 .SHORT TERM...Tonight through Friday night...Upper trough off the coast has closed of a low (near 36N/138W at 2 PM MST). The low is headed toward southern Calif while the northern part of the trough moves rapidly inland along the Canadian border, getting all the way to North Dakota by Saturday morning. The portion that comes through our CWA will provide only minimal support for the surface cold front expected to pass through our CWA late Thursday night and Friday morning. Even so, the front should still be able to scour our weak surface inversion. But before that happens Thursday will be another very mild day with high temps close to record highs for Nov 13. Pre-frontal southwest winds will gust 25 to 30 mph Thursday afternoon in eastern OR and the Southwest ID highlands. The weakening front will bring only slight cooling Friday. Pcpn forecasts have changed only slightly but look a little wetter in western ID late Thursday night and Friday morning. Total pcpn Thursday through Saturday morning is still expected to range from .25 to .50 inch in the Boise Mountains and West Central Idaho mountains, with around .10 inch in the Snake Basin, .05 to .15 inch in the eastern OR valleys, and .15 to .25 inch in the OR mountains. Snowfall will be minimal with snow levels staying above 7000 feet MSL during most of the pcpn. .LONG TERM...Saturday through Wednesday...A brief break in the unsettled weather is on tap for Saturday; with the jet stream to our north, and a closed-low off the SoCal coast, keeping most of our area dry (aside from isolated showers over higher terrain in Valley County). This dry period is shortlived, however, as the SoCal closed low introduces some fun into the forecast. Come Sunday, a trough digging down from the Gulf of Alaska switches flow aloft to southwesterly, which will help steer the SoCal low to the northeast as it fills in and embeds back into the main flow. The major ensemble means have this bringing moisture and dynamics to support precipitation come Sunday. This system will be immediately followed by the aforementioned Gulf of Alaska trough, prolonging the unsettled weather into early next week. Snow levels will lower to 4-5 kft MSL through the day Monday allowing for a couple of inches of snow along ridgelines, and perhaps even a dusting in higher elevation towns. Temperature will start out at 5-10 degrees above normal on Saturday, lowering to near normal on Monday following a cold frontal passage. && .AVIATION...VFR with high clouds. LLWS possible overnight in E-Oregon, especially near KBNO. Isolated virga showers this afternoon/evening. Surface winds: Variable up to 10 kt. Winds aloft at 10kft MSL: SW 15-25 kt. KBOI...VFR. Surface winds: SE 5-10 kt. && .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