Area Forecast Discussion
Issued by NWS Boise, ID
Issued by NWS Boise, ID
538 FXUS65 KBOI 200921 AFDBOI Area Forecast Discussion National Weather Service Boise ID 321 AM MDT Thu Jun 20 2024 .SHORT TERM...Today through Saturday night...A weak upper-level trough remains over the forecast area today, maintaining warm and dry conditions. Expect mostly clear skies, though smoke from a wildfire in southwest Owyhee County may cause hazy conditions this afternoon across southwest Idaho. Temperatures in the lower valleys will reach the low 90s today. A weak trough will pass through tonight into Friday, limiting the warming on Friday to 2-4 degrees above Thursdays high temperatures. High- resolution models indicate enough moisture for cumulus cloud development along the Idaho/Nevada border. A Pacific system will reach the British Columbia coast on Saturday, forming a ridge and creating a southwesterly flow aloft over the forecast area. This could bring the warmest temperatures of the year so far, with a 40-50% chance of the Treasure Valley seeing maximum temperatures reach 100 degrees or higher on Saturday. Historically, Boise`s first 100-degree day typically occurs around July 7th, though in 5 of the last 11 years, it has happened in June. .LONG TERM...Sunday through Thursday...Hot temperatures will persist on Sunday, with highs forecasted to reach around 100 degrees in the Treasure Valley. The Pacific system from the Gulf of Alaska will move across British Columbia on Sunday, bringing a surface cold front toward the forecast area from the northwest. This front, along with cooler temperatures, will not reach the area until Monday, providing a brief respite from the heat. Temperatures will drop into the mid-90s on Monday. However, hot and dry weather will continue through Wednesday. A much stronger Gulf of Alaska trough is expected to move inland starting Thursday, initiating a cooling trend. Ensembles show good agreement on this shift occurring late next week. && .AVIATION...VFR under clear skies. Surface winds: E-S up to 15 kt. Winds aloft at 10kft MSL: S-SE 10-15 kt. KBOI...VFR. Easterly winds less than 10 kt switching to the northwest around 18z. Weekend Outlook...VFR with clear skies. Hot temperatures will bring high density altitudes Saturday and Sunday. Light south-southwesterly winds. && .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 SHORT TERM...JDS LONG TERM....JDS AVIATION.....JDS