textproduct: Boise

UPDATE

Updated aviation discussion.

KEY MESSAGES

- Continued hot, dry, and smoky into Wednesday.

- Gradual cooling through the week.

- Increasing chance of showers and thunderstorms Thursday and beyond, especially on the Idaho side.

SHORT TERM /Through Wednesday Night/

Issued 221 AM MDT MON AUG 10 2026 Near zonal flow aloft today will begin to turn more southwesterly as troughing deepens near the west coast. Lingering monsoonal moisture today should remain just south and east of our area. As such, any isolated showers/thunderstorms this afternoon and Tuesday afternoon should also remain just outside of our area. This will begin to change, however, come Wednesday as the southwesterly flow allows for monsoonal moisture to push back across the area. Come Wednesday afternoon, this moisture will be playing with the Nevada border, which will allow for isolated showers/thunderstorms to develop near the Nevada border. With a dry boundary layer, gusty winds will be the primary hazard out of storms that develop. This moisture will continue to push north into our area beyond Wednesday.

Otherwise, the short-term period will continue to be hot, smoky, and breezy. Low elevation temperatures will generally be in the low to mid 90s with mountain valleys in the mid to high 80s.

LONG TERM /Thursday through Monday/

Issued 221 AM MDT MON AUG 10 2026 The long-term period is looking to be more active (especially across southwest Idaho). Monsoonal moisture will continue to push north through the end of the week, with LREF mean PWATs increasing to around the 90th percentile of climatology. Come thursday afternoon, chances of showers and thunderstorms will overspread the majority of southwest Idaho and portions of eastern Oregon, aided by the upper level trough and shortwave. Model soundings indicate elevated instability continuing into Friday morning, so some nocturnal thunderstorms can't be ruled out overnight Thursday. Showers and afternoon thunder will continue into the weekend, especially over the Central Idaho Mountains and near the Nevada border. With atmospheric moisture increasing, heavy rain will become more of a threat, especially over steep terrain and recently burned areas. Chances of showers and thunder will begin to taper off over the weekend as the shortwave exits our areas. This is barring higher terrain where isolated to scattered afternoon thunderstorms will remain. With general troughing continuing near the west coast, an active pattern could continue beyond the weekend. Temperatures will be warm through the extended, but generally near normal, even leaning below normal by the end of the week.

AVIATION /12Z Monday through Tuesday/

Issued 407 AM MDT MON AUG 10 2026

Generally VFR with periods of MVFR conditions this morning, mainly in E-Oregon. Wildfire smoke continuing to impact visibility, with improvement this afternoon. Periods of mtn obscuration. High density altitude due to heat this afternoon. Surface winds: variable up to 10 kt this morning. Then W-NW 10-20 kt this afternoon. Winds aloft at 10kft MSL:

KBOI...VFR with smoke resulting in some visibility degradation and foothill obscuration. Smoky conditions improving this afternoon. Surface winds: light and variable this morning. Becoming NW 8-12 kt with gusts to around 18 kt this afternoon.

BOI WATCHES/WARNINGS/ADVISORIES

ID...Air Quality Alert until 1 PM MDT this afternoon for IDZ011>015- 028-029-033. OR...Air Quality Alert until 1 PM MDT /noon PDT/ this afternoon for ORZ061>064.