Area Forecast Discussion
Issued by NWS Boise, ID
Issued by NWS Boise, ID
767 FXUS65 KBOI 031552 AFDBOI Area Forecast Discussion National Weather Service Boise ID 952 AM MDT Wed Jul 3 2024 .DISCUSSION...Wednesday through Thursday temps will still be just below normal to about normal with clear skies. This afternoon we`re expecting windy conditions in much of the Snake Plain and southern Idaho. Gusts of 30-40 mph are expected in the Magic Valley and Camas Prairie with 20-30 mph elsewhere. Gusty winds combine with very dry air to result in critical fire weather conditions across portions of southern Idaho, particularly in the lower elevations where fuels are driest. Otherwise sunny skies and warm temperatures. Still closely tracking the development of a strong upper ridge building over the western CONUS. This will bring a prolonged period of very hot temperatures, very dry air, and clear skies. Expect an Excessive Heat Watch to come out with the afternoon package, as not only are the afternoon highs significant, but the heat continues for the foreseeable future. Many records are being threatened by our current forecasted highs, and the areas of Major HeatRisk are extensive by early next week. Again, more details to come with the Watch for the afternoon package. && .AVIATION...VFR. High density altitude will become a factor by the weekend into much of next week. Surface winds: N-NW 5-15 kt with gusts to 20 kt. West winds gusting to 25-35 kt after 03/15Z at KTWF/KJER. Winds aloft at 10kft MSL: W-NW 15-30 kt. KBOI...VFR with clear skies. Surface winds: NW 7-11 kt becoming NW 11-13 kt with gusts to 25 kt possible after 03/17Z. && .PREV DISCUSSION... SHORT TERM...Today through Friday night...Dry northwest flow will prevail through the end of the week. A shortwave trough will pass by to our north today. The main impact of this system for our area will be gusty winds across southern Idaho as the surface pressure gradient increases with the passage of the trough. Gusts of 30-40 mph are expected in the Magic Valley and Camas Prairie this afternoon, with 20-30 mph elsewhere. Gusty winds will combine with very dry air to result in critical fire weather conditions across portions of southern Idaho, particularly in the lower elevations where fuels are dry. Otherwise, expect sunny skies and temperatures similar to yesterday, or a couple degrees below normal. A strong upper level ridge along the coast will slowly build inland through Friday. This will bring a continuation of sunny skies and breezy winds for the 4th of July and Friday, although winds will not be as strong as today. Highs will warm several degrees each day, with lower valley highs around 90 on Thursday and the mid to upper 90s on Friday. Dry air and clear skies will allow for cool overnight temperatures. LONG TERM...Saturday through Wednesday...Confidence remains high that a long-duration heat wave will commence this weekend and persist into next week. An intense high pressure ridge near the west coast gradually moves eastward as the axis reaches our area by the middle of next week for continued dry conditions. High temperatures will likely (> 60 percent chance) exceed 100 degrees in the lower valleys starting on Saturday with temperatures warming a degree or two each day, peaking on next Tuesday or Wednesday as highs likely exceed 105 degrees in some areas, including the Treasure Valley. Some locations may reach or exceed record highs. Fortunately, the air mass will be dry allowing for overnight lows to dip into the 60s providing temporary relief through the early morning hours. && .BOI WATCHES/WARNINGS/ADVISORIES... ID...Red Flag Warning until 9 PM MDT this evening IDZ424-426. OR...None. && $$ www.weather.gov/Boise Interact with us via social media: www.facebook.com/NWSBoise www.twitter.com/NWSBoise DISCUSSION...JM AVIATION.....JR SHORT TERM...ST LONG TERM....BW