textproduct: Boise

UPDATE

Updated aviation discussion.

KEY MESSAGES

- Smoky conditions continue through the week.

- Warming this week brings temperatures above 100 degrees by Thursday.

- Increased winds Friday through the weekend.

SHORT TERM /Through Thursday Night/

Issued 339 AM MDT TUE AUG 4 2026 Upper-level ridging will continue to build into the Pacific Northwest. Increasing maximum temperatures day over day are expected, with most areas seeing an increase of 5 degrees per day. Temperatures climb from 5 degrees below normal to 5-10 degrees above normal by the end of the short term. Some moderation in temperatures from localized smoke density is possible, although difficult to depict quantitatively. Speaking of smoke, continued impacts across the area are expected as north/northwesterly winds aloft transport smoke from parts of Oregon and Washington. While breezy winds and diurnal heating will provide some relief in the afternoons, models agree that the smoke will be sticking around for now.

LONG TERM /Friday through Tuesday/

Issued 339 AM MDT TUE AUG 4 2026 While the upper-level ridge is expected to remain over the Desert Southwest, flattening of the ridge over the Pacific Northwest is forecast going into the weekend. Hot temperatures will be sticking around, with the larger concern being fire weather. Afternoon wind gusts will increase, and despite the switch to west/southwesterly flow aloft, no precipitation is expected. The synoptic pattern looks similar at the beginning of next week as well, however clusters have the upper-level ridge retreating east towards the Four Corners region, allowing some moisture to make it into the Great Basin. Time will tell if we are fortunate enough for it to make it this far north. Otherwise, smoky conditions will continue from area wildfires.

AVIATION /12Z Tuesday through Wednesday/

Issued 540 AM MDT TUE AUG 4 2026

Reduced visibility due to wildfire smoke, with areas of MVFR-IFR and mountain obscuration. Surface winds: variable up to 12 kt this morning. This afternoon becoming NW 5-12 kt, with gusts near 20 kt in southern Idaho. Winds aloft at 10kft MSL: NW-W 5-15 kt.

KBOI...MVFR-IFR visibility will be common due to wildfire smoke. Temporary slight improvement during late afternoon Tuesday. Surface winds: variable or southerly 3-6 kt through morning, returning to NW 5-12 kt this afternoon.

BOI WATCHES/WARNINGS/ADVISORIES

ID...Air Quality Alert until 2 PM MDT Friday for IDZ011>015-028-029- 033. OR...Air Quality Alert until 1 PM MDT /noon PDT/ this afternoon for ORZ061>064.