Area Forecast Discussion
Issued by NWS Boise, ID
Issued by NWS Boise, ID
380 FXUS65 KBOI 070931 AFDBOI Area Forecast Discussion National Weather Service Boise ID 331 AM MDT Tue May 7 2024 .SHORT TERM...Today through Thursday night...A cold front has moved through the area as a deep upper level trough remains over the WY/MT/SD. The instability from the cold air aloft (500mb temps around -27C) will keep a threat of showers over the area today, mainly focused over the mountains through this afternoon and evening. Temperatures will be around 15 degrees below normal today with the cool airmass. Windy conditions expected, with the strongest winds in the Magic Valley and southern Twin Falls County this afternoon, where a wind advisory remains in effect. Upper level ridging over the Pacific NW and southwest Canada will cut off the cold air source from the Gulf of Alaska, and the trough will weaken and remain stationary over the WY/MT/SD area through the short term. Wrap around moisture will keep a threat of showers over the ID mountains on Wednesday, but the rest of the area will remain dry, with about 10 degrees of warming on Wednesday. Breezy west to northwest winds continue on Wednesday, but the upper level winds shift to the north/northeast, which keeps the winds below advisory levels. The upper level ridge expands over the Pacific NW on Thursday, with northeast flow aloft keeping temperatures from realizing the full potential of the ridge. Record breaking temperatures possible over portions of the Pacific NW and British Columbia, but the center of the ridge will be north and west of our area, where the warmer temperatures are. Temperatures warm another 10 degrees on Thursday with dry conditions. .LONG TERM...Friday through Tuesday...An east-west oriented ridge will be in place to start Friday, and will dominate our weather at least into Sunday. This will continue both the dry conditions and the warming trend. Temps will be 5-10 degrees above normal Friday, rising to 10 degrees above normal Saturday, and 10-15 degrees above normal Sunday. There`s now a >90% chance of exceeding 80 degrees Sunday for most of the Treasure Valley. Slight cooling is expected Mon-Tue, but temps should remain above normal. The vast majority of ensemble members keep the area dry through Tuesday, but the deterministic GFS brings a weak shortwave trough to the region. If this low-probability solution ends up verifying, we will have a chance for showers. && .AVIATION...VFR-MVFR showers continue, mainly south and east of Boise. Mountains obscured. Isolated IFR and local LIFR possible in snow above 4-5kft MSL. Showers will increase in coverage this afternoon, but not be as strong as Monday. Sfc winds: W-NW 10-20 kt, increasing to W-NW 15-25 kt with gusts near TWF/JER to 35-45 kt after 15z. FL100 winds: W-NW 20-35 kt. KBOI...VFR. Scattered showers this morning, tapering off around 12z/Tue, but isolated showers will redevelop this afternoon. Only about a 10% chance for one to hit the airport. Sfc winds: NW 10-20 kt with gusts to 30 kt after 18Z. && .BOI WATCHES/WARNINGS/ADVISORIES... ID...Wind Advisory from noon today to 9 PM MDT this evening IDZ016-030. OR...None. && $$ www.weather.gov/Boise Interact with us via social media: www.facebook.com/NWSBoise www.twitter.com/NWSBoise SHORT TERM...KA LONG TERM....SP AVIATION.....SP