Area Forecast Discussion
Issued by NWS Boise, ID
Issued by NWS Boise, ID
256 FXUS65 KBOI 120239 AFDBOI Area Forecast Discussion National Weather Service Boise ID 839 PM MDT Tue Jun 11 2024 .DISCUSSION...Satellite imagery has detected at least four active wildfires in Southwest Idaho: two near Twin Falls, one in south Ada County, and one south of Jordan Valley. As of 7:30 PM MDT, all fires have been reported to be less than 10 acres. Smoke is not expected to be an issue across southern Idaho at this time due to an upper-level low moving across southern Alberta, Canada, accompanied by a dry cold front that has already reached parts of southeast Oregon. This front will continue moving southeast, reaching Ontario around 10 PM MDT, Boise around 11 PM MDT, Mountain Home around 1 AM MDT, and Twin Falls/Jerome around 3 AM MDT. The highest winds tonight will be between Baker Valley and the Lower Treasure Valley. Baker City has already reported wind gusts up to 37 MPH, and similar gusts are expected to reach Ontario. Gusts will be slightly lower as the front moves up the Upper Treasure Valley and Western Magic Valley, with gusts up to 20-25 MPH. The passage of the front overnight will result in temperatures about 5 degrees cooler on Wednesday. Winds have been updated to reflect current observations and the latest high-resolution models for tonight into Wednesday morning. The new data indicates slightly higher wind speeds than previously forecasted. An updated forecast will be issued shortly. && .AVIATION...VFR and mostly clear. Surface winds: W-NW 5-15 kt. Gusts 20-30 kt KBKE-KONO-KMUO late tonight/early Wednesday as a dry cold front moves through. Winds aloft at 10kft MSL: W-SW 15-30 kt. KBOI...VFR under clear skies. Surface winds: NW 7-13 kt. Gusts up to 20 kts between 05Z and 08Z. && .PREV DISCUSSION... SHORT TERM...Tonight through Thursday night...A weak north Pacific upper trough will bring about 5 degrees cooling Wednesday as it moves inland north of our CWA. Thursday looks as hot as today as a short wave upper ridge comes inland ahead of a deep upper trough from the Gulf of Alaska. Generally clear skies until Thursday when clouds begin in southern zones. Models develop enough instability near the ID/NV/UT tri-point for a 10-20 percent chance of high-based thunderstorms Thursday evening. Tonight and Wednesday night will be seasonably cool with dry air and clear skies. No significant smoke indicated by HRRR model. Thursday night looks several degrees warmer with cloud cover and higher dew points. Winds will be light except in southern Harney and Malheur Counties Thursday afternoon/night, when west winds blow 15 to 25 mph with gusts to 30 mph. LONG TERM...Friday through Tuesday...A deep upper trough from the Gulf of Alaska will come inland and through our CWA Friday through Tuesday with much cooler air. Initial surface cold front will pass through Friday. Pre-frontal gusty southwest winds will shift to west/northwest 10-20 mph. High temps Friday will be in the upper 70s through 80s. A second cold front will increase northwest winds to 15-25 mph with afternoon gusts 25 to 35 mph Saturday in open terrain. Highs Saturday will lower to the mid 60s to mid 70s, then mainly 60s Sunday and Monday, with breezy northwest winds continuing. Models keep pcpn generally north of our CWA with the best chance (20-40 percent) Sunday night in the central Idaho mountains. Model consistency breaks down Monday with ECM bringing the main trough axis through our CWA while GFS leaves it off the northwest coast. Consensus for now is with the ECM for continued cool, breezy weather Tuesday. && .BOI WATCHES/WARNINGS/ADVISORIES... ID...None. OR...None. && $$ www.weather.gov/Boise Interact with us via social media: www.facebook.com/NWSBoise www.twitter.com/NWSBoise DISCUSSION...JDS AVIATION.....JDS SHORT TERM...LC LONG TERM....LC