FXUS65 KBOI 271604 AFDBOI Area Forecast Discussion National Weather Service Boise ID 1004 AM MDT Mon Oct 27 2025 .DISCUSSION...We're starting with mostly clear skies this morning on the backside of the upper trough. Afternoon instability will lead to cumulus over higher terrain, and a slight chance of showers in the mtns north of Baker City, McCall and Warm Lake. Winds will remain light for most locations, with the western Magic Valley and Camas Prairie keeping a steady 10-15 mph, gust to 20 mph wind through the day. Hard freeze still on tap for tonight across all zones. Current forecast is on track so now update. && .AVIATION...Lingering MVFR In isolated snow showers in the mountains, with snow levels of 3.5-4.5 kft MSL through the day. Otherwise, VFR today with a few mid level clouds. Surface winds: N-W 5-12 kt. Winds aloft at 10kft MSL: W-NW 10-20 kt. KBOI...VFR. Surface winds NW 5-10 kt today, becoming SE 4-8 kt tonight. && .PREV DISCUSSION... SHORT TERM...Today through Wednesday night...Rain and snow showers in ID early this morning will be the last pcpn for several days, except for possible flurries in northern-most mountains Wednesday morning. The main upper trough will exit east this morning as an upper ridge comes in from the Pacific. A faster-moving upper trough from the Gulf of Alaska will race inland along the Canadian border Wednesday while the slower- moving upper ridge stays over our CWA. The trough is the reason for the possible flurries far north Wednesday. West winds will increase to 15 to 25 mph with gusts to 30 mph in south-central Idaho behind today's departing upper trough, but will decrease tonight in all areas as skies clear. Strong radiational cooling will then take place and Tuesday morning will be the coldest of the season so far. Patchy fog will develop in the valleys overnight and last into mid-morning Tuesday as a mild inversion sets up. The incoming upper ridge will allow daytime high temps to warm faster in the mountains than in the valleys starting Tuesday, and patchy valley fog may be slow to clear after the cold nights and low sun angle of late October. LONG TERM...Thursday through Monday...The long term will start out dry with our area under near zonal flow, resulting from a deepening Alaskan low and high pressure over SoCal. Throughout the day Friday, a moist plume of Pacific moisture will begin to advect over our area ahead of an upper level shortwave and surface cold front associated with the aforementioned low. High clouds will increase across our area Friday as a result of this moisture advection. While the bulk of the moisture is looking to remain to our north, there will be enough residual moisture to support precipitation in our area. Ensemble mean PWATs are progged to reach the around the 90th percentile. This will support elevated precipitation chances north of a line from (roughly) Fairfield/ID to Wagontire/OR. Precipitation chances will range from 20% to 50%, increasing as you move north from that line. The weekend will also be breezy as the pressure gradient tightens. Our area will begin to dry out through Sunday as weak ridging begins to build in again. Temperatures will be seasonable for this time of year, although will lean above normal over the coming weekend. Also, with our area on the periphery of ridging some uncertainty is introduced regarding late week temperatures. && .PRELIMINARY POINT TEMPS/POPS... Baker City 21 51 24 55 / 0 0 0 0 Boise 32 55 34 56 / 0 0 0 0 Burns 16 53 21 58 / 0 0 0 0 Caldwell 29 56 32 57 / 0 0 0 0 Fairfield 12 46 17 54 / 0 0 0 0 Idaho City 17 53 21 57 / 0 0 0 0 Jerome 26 48 31 54 / 0 0 0 0 McCall 16 44 21 48 / 0 0 0 0 Mountain Home 27 54 30 58 / 0 0 0 0 Ontario 27 56 28 57 / 0 0 0 0 Rome 21 57 25 59 / 0 0 0 0 Twin Falls 27 48 29 54 / 0 0 0 0 && .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 DISCUSSION...DG AVIATION.....JM SHORT TERM...LC LONG TERM....NF