Area Forecast Discussion
Issued by NWS Boise, ID
Issued by NWS Boise, ID
055 FXUS65 KBOI 011528 AFDBOI Area Forecast Discussion National Weather Service Boise ID 928 AM MDT Tue Jul 1 2025 .DISCUSSION...Satellite, radar and lightning detection networks are showing isolated thunderstorms over portions of Harney County and western Malhuer County. These thunderstorms appear to be weakening as they move northward, mostly over open range land. However, there is about a 15 percent chance that the Burns-Hines area could hear a rumble of thunder with these storms this morning. The morning sounding at Boise, shows some mid level moisture with very dry conditions at the surface, so little if any rain will reach the ground as it evaporates leaving virga beneath the cloud. Expect gusty winds in the vicinity of any virga. The atmosphere becomes more unstable this afternoon, especially in the Magic Valley of southern Idaho, where isolated thunderstorms could produce gusty winds until around sunset. A heat advisory remains in effect this afternoon for the Treasure Valley and Weiser River Valley where afternoon high temperatures will be over 100 degrees. && .AVIATION...Mainly VFR. Isolated showers and thunderstorms this morning across SE Oregon with gusts to 30 kt. Additional isolated showers and thunderstorms this afternoon and evening across SE Oregon and the higher terrain of SW Idaho with gusts to 45 kt. High density altitude due to heat. Surface winds: NW-NE 5-15 kt, except SW 10-20 kt this afternoon along the NV border and in the central ID mountains. Winds aloft at 10kft MSL: SE-SW 10-20 kt. KBOI...VFR. High density altitude due to heat. Surface winds: variable less than 8 kt this morning, becoming NW 5-10 kt this afternoon. && .PREV DISCUSSION... SHORT TERM...Today through Thursday night...An upper level ridge will move slowly east of the area this afternoon, allowing our hottest day of the week. A Heat Advisory is in effect today from 11 AM MDT to 8 PM MDT for the lower elevations and was not changed in this forecast. The temperature forecast to today`s highs has changed very little over the past day, with highs at or above 100 degrees forecast over most areas of elevation below around 3000 ft MSL. Showers and thunderstorms (15-30% chance) are expected to form today into tonight, with gusts to 50 mph possible. The best chance for strong gusts this afternoon is across southern Twin Falls County and the western Magic Valley. This evening, the best chance is across Harney County, possibly getting up into Baker County as well. Wednesday, even stronger storms are forecast, and SPC has put roughly the NW half of the CWA into the "marginal" category. Wind gusts to 60 mph are possible from mid-afternoon well into the evening. Strong gusts are possible in the western Magic Valley as well, even though that area is not presently covered by the marginal risk. Temperatures will not be quite as hot Wednesday, with only the lowest elevations along the Snake River in the Upper Treasure Valley forecast to reach 100. Storms are in the forecast again Thursday and Thursday night (20-60% chance), mainly in the Idaho side, with gusts to 50 mph possible. LONG TERM...Friday through Tuesday...Confidence has increased in the long-term forecast with latest runs. Deterministic models show a shortwave moving through the area with a threat of scattered thunderstorms. The highest chances for precip with this system are over the Idaho Central Mtns, including the Boise and West Central mtns at about 50% chances. In Idaho lower elevations and parts of SE and E Oregon Precipitation chances are lower at about 20%. This shortwave seems to be the event that the EC and GFS deterministic models are most excited about in terms of thunderstorms relative to other days in the forecast. Lightning and outflow winds will be the primary hazards out of thunderstorms. The forecast following Friday appears to quiet down, as a new CA low develops and puts us under drier SW flow and warms temps through Tuesday. We warm from near normal on Friday to about 10 degrees above normal on Tuesday, with Snake Plain highs approaching 100 degrees. && .BOI WATCHES/WARNINGS/ADVISORIES... ID...Heat Advisory until 8 PM MDT this evening IDZ012-014-033. OR...Heat Advisory until 8 PM MDT /7 PM PDT/ this evening ORZ064. && $$ www.weather.gov/Boise Interact with us via social media: www.facebook.com/NWSBoise www.x.com/NWSBoise DISCUSSION...JB AVIATION.....ST SHORT TERM...SP LONG TERM....MC