Area Forecast Discussion
Issued by NWS Boise, ID
Issued by NWS Boise, ID
489 FXUS65 KBOI 231518 AFDBOI Area Forecast Discussion National Weather Service Boise ID 918 AM MDT Mon Sep 23 2024 .DISCUSSION...Cirrus clouds coming in from the northwest as a warming Pacific upper ridge builds inland. The ridge will move over our CWA Tuesday and east of us Wednesday. Wednesday will be the warmest day with highs now forecast 90 to 93 degrees in the Treasure Valley, 80s in other valleys and basins, and 70s in the mountains. A cold front Wednesday evening looks strong enough for a 10-20 percent chance of thunderstorms north of Baker/OR- McCall/ID. Current forecast has all this. No updates. && .AVIATION...VFR. High clouds will diminish late Monday. Surface winds: Becoming mostly NW 5-15kt with afternoon gusts to 25kt east of KMUO. Light and variable overnight. Winds at 10kft MSL: North-northeast at 10-15kt. KBOI...VFR. Scattered to broken cirrus. Light winds this morning becoming northwest 5-15kt this afternoon. && .PREV DISCUSSION... SHORT TERM...Today through Wednesday night...A dry weak cold front will finish moving through the area this morning, ushering in increasing NW winds by this afternoon, especially from around Mountain Home east toward Twin Falls and Jerome. An upper level ridge will build over the region tonight and then move quickly off to the east Tue and Tue night. This will allow dry and warmer SW flow aloft to move in. Temps will warm each day, reaching a peak Wed with readings around 15 degrees above normal. There may be enough moisture by Wed night for showers and thunderstorms across the north, and the forecast PoP is trending slowly upwards in/near Baker County. This latest forecast has values of 5-20% there, mainly Wed evening. Otherwise, the short term period is dry. After the previously mentioned increase in NW winds this afternoon, winds will be fairly light Tuesday. However, Wed will bring an increase in SW winds across much of SE Oregon, Owyhee County, and the higher elevations of our Idaho mountains. LONG TERM...Thursday through Monday...Dry southwest flow aloft will remain over the region Thu through Sat night. A shortwave trough is likely to move through Sun, but models differ significantly on the strength and impact of this trough. It is not forecast to bring any precipitation according to the latest NBM. However, if the stronger members of the ensembles come to pass, it would bring showers and perhaps thunderstorms across our northern zones Sunday, along with a breezy day across most of the region. Monday is expected to be dry and cooler, but how much cooler will depend on the strength of the system. At this time, the forecast is for a return to normal Monday after an week of above-normal temperatures. && .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...LC AVIATION.....JR SHORT TERM...SP LONG TERM....SP