Area Forecast Discussion
Issued by NWS Boise, ID
Issued by NWS Boise, ID
405 FXUS65 KBOI 150335 AFDBOI Area Forecast Discussion National Weather Service Boise ID 835 PM MST Fri Nov 14 2025 .DISCUSSION...No forecast changes through Saturday, but beginning Saturday evening latest models show more definite pcpn-shadowing (i.e., less rain) in the Snake Basin, and a better-defined moist lobe and more rain in eastern OR, both features lasting through Sunday night. PoP, QPF, and weather grids have been updated. Remainder of forecast unchanged. && .AVIATION...VFR. Morning fog will be minimal due to high clouds. Surface winds: variable up to 12 kt. Winds aloft at 10kft MSL: SW to W 20-35 kt, then S to SW 5-15 kt after 15/18Z. KBOI...VFR. Rain chances increase Sat night. Surface winds: variable or SE up to 8 kt. Sunday Outlook...Lowering ceilings late Saturday, with rain arriving from S to N Saturday night and Sunday. VFR/MVFR in valleys, and MVFR to LIFR in mountains, in precip and low clouds. Mtns becoming obscured. Snow levels 8.5k-9.5k feet MSL, lowering to 7.5k-8.5k feet Sunday PM. Surface winds: variable 5-15 kt Sat night, then SW-SE 5-15 kt with gusts to 20-30 kt beginning late Sun morning. && .PREV DISCUSSION... SHORT TERM...Tonight through Sunday night...High pressure will build over the area tonight into Saturday. This will bring dry conditions with light winds. Partly cloudy skies and lingering moisture from last night`s rain will allow patchy fog to develop tonight mainly in mountain valleys. Highs on Saturday will be 10-15 degrees above normal under partly to mostly sunny skies, making for a pleasant afternoon. Quiet weather won`t last long as a cutoff low currently off the coast of southern California moves inland and then north through western Nevada late Saturday into Sunday ahead of a trough off the coast. This cutoff low will have a deep moisture tap and will boost our precipitable water values to around the 95th percentile for the time of year. Rain will increase from south to north across our area late Saturday night and Sunday morning, with a 60-90% chance of showers continuing through Sunday night. A widespread 0.10-0.50" of rainfall looks likely with this system, with a 10-20% chance for up to 1.00" in some locations due to surface/mid-level convergence near the low pressure center, and in the mountains where orographics will boost totals. Snow levels will remain high through Sunday night, lowering from 8000-9000 feet early Sunday to around 7000 feet Sunday night. Winds will be breezy, and increased precipitation/ clouds will cool temperatures by several degrees. LONG TERM...Monday through Friday... Considerable uncertainty in the long term. Precipitation chances linger through Monday as a shortwave move NE across the Great Basin. Guidance is continuing to indicate that the trough that worked to steer that shortwave NE will close off into a low off the SoCal coast. Roughly 45% of ensemble members (mostly out of the GFS suite) show this solution, with 35% of members (mostly out of the Euro suite) keeping the trough open and swinging it across our area. In the two scenarios, the GFS would keep our area warmer and drier whereas the Euro would keep us cooler and wetter. However, in the GFS solutions, a shortwave grazes us to the north, keeping in phase with the SoCal low. All that said, this gives way to widespread showers on Monday, with elevated precipitation chances (20-60%) hanging on across higher terrain through early Wednesday. The major model ensembles show brief ridging building in through Wednesday which will dry out our area ahead of the next system. Late next week, another trough will dig down from the Gulf of Alaska which will bring cooler temps and precipitation. However, there is much to be resolved with regard to exact timing and the strength of the system. Higher temperatures throughout the period are beginning to reflect the warmer scenarios, with high temp forecasts to be around 5 degrees above normal. && .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...LC AVIATION.....SH SHORT TERM...ST LONG TERM....NF