Area Forecast Discussion
Issued by NWS Boise, ID
Issued by NWS Boise, ID
236 FXUS65 KBOI 300238 AFDBOI Area Forecast Discussion National Weather Service Boise ID 838 PM MDT Wed May 29 2024 .DISCUSSION...Current forecast is on track with clearing skies tonight, followed by sunny, cool, and less windy weather Thursday as today`s upper trough exits east. A weak Pacific upper ridge will bring sunny skies and about 8 degrees warming Friday. Then mostly cloudy but another 5 degrees warmer Saturday ahead of a weak incoming Pacific trough. The trough will bring a surface cold front through our CWA Saturday evening, along with a 15-30% chance of showers and thunderstorms in northern mountains Saturday afternoon and evening. However, little if any cooling will be felt Sunday. No updates. && .AVIATION...VFR. Surface winds: W-NW 5-15 kt with gusts of 20-30 kt, becoming variable 5-15 kt overnight. Winds aloft at 10k ft MSL: W-NW 15-30 kt. KBOI...VFR. Winds generally NW 5-15 kt through Thursday. && .PREV DISCUSSION... SHORT TERM...Tonight through Friday night...An upper level trough centered over our area is moving eastward, resulting in breezy conditions this afternoon/evening and a few showers over northern Valley County. Gusts between Mountain Home and the Magic Valley are roughly between 30-45 mph, while elsewhere in the Snake Plain gusts will be around 20-30 mph. There is a small chance (10-15%) of lightning in the showers in Valley County, so strikes are likely to be isolated occurrences if any. Showers will dissipate around midnight, and that will be the last of precipitation in the short term. As the trough gives way to a ridge, dry air will settle in and skies are set to be mostly clear. Temperatures will be around 10 degrees below normal today/Thursday, and rise to about normal on Friday. LONG TERM...Saturday through Wednesday...Models are continuing to agree on the progression of large scale features. On Saturday the first of two troughs moves into our area, bringing just a 15-30% chance of showers across NE Oregon and central Idaho. Conditions will be breezy Saturday afternoon as the trough drags a weak cold front through. Sunday will be partly cloudy and a little breezy in the Magic Valley before the next trough moves in on Monday. This trough is the stronger of the two mentioned, and brings in much more moisture. These characteristics have led to a steady increase in precipitation potential on Monday. Precipitation chances in the south near Rome/Twin Falls are roughly 30%, and increase uniformly to the north near Baker City/McCall where chances are 70-80%. Monday will be mostly cloudy and the best chance for rain is forecast to be around noon. This will limit convective potential in the afternoon somewhat, but summertime temperatures and unsettled conditions still support a 15-25% chance of thunderstorms. This trough brings another cold front, supporting continued breezy conditions. Temperatures in the long term trend a little lower each day with the progressive fronts, dropping from 5 degrees above normal on Saturday to 5 degrees below normal by Tuesday. However, models still show high pressure building in late next week. While the position and strength vary, there will be a significant warm up on Wednesday back to 5 degrees above normal. && .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.....SH SHORT TERM...JM LONG TERM....JM