textproduct: Boise

UPDATE

Updated aviation discussion.

KEY MESSAGES

- Warm and dry conditions will persist over the next several days.

- Smoky conditions at times.

- Slightly cooler with near-normal temperatures through midweek.

SHORT TERM /Through Tuesday Night/

Issued 331 AM MDT SUN JUL 26 2026 Strong southwest flow aloft will steer some remnant monsoonal moisture across the easternmost portions of our area over southwest ID. This pattern will continue chances of showers/thunderstorms through the morning, before drier air moves into the area today with slightly cooler temperatures and continued low humidities. Winds aloft will be weaker today and Monday. As such, generally lower afternoon breezes will be expected today through Tuesday. Gusty northwest valley winds from Baker Valley OR to the lower Treasure Valley areas of the ID-OR border will be expected each evening from tonight through Tuesday night. These heightened northwest breezes will likely bring denser smoke from wildfires over eastern OR into most of the Treasure Valley, especially during the overnight and morning hours.

LONG TERM /Wednesday through Sunday/

Issued 331 AM MDT SUN JUL 26 2026 A strong high pressure system sitting off the four corners region, and a trough over British Columbia, will keep our area under southwesterly flow aloft. Monsoonal moisture will remain south and east of our area in this pattern, leading to a hot, dry, and breezy long-term period. Near (leaning above) normal temperatures will warm to around 5 degrees above normal come Thursday, as the aforementioned high pressure system shifts west over the Great basin. Sunday may see a cooldown to near-normal temperatures, depending on how far down troughing from the northwest coast reaches into our area.

AVIATION /18Z Sunday through Monday/

Issued 1043 AM MDT SUN JUL 26 2026

Wildfire smoke resulting in MVFR/IFR visibilities across the area. Visibilities should increase slightly in the afternoon, before degrading again overnight and early Mon/AM. High density altitude this afternoon due to heat. Surface winds: NW-SW 5-15 kt with afternoon gusts to 20-25 kt in E-Oregon and higher terrain of SW-Idaho. Winds aloft at 10kft MSL: SW 15-30 kt.

KBOI...Visibility degraded to MVFR/IFR due to wildfire smoke. Some improvement this afternoon, before smoke settles in again over night and early Mon/AM. High density altitude this afternoon due to heat. Surface winds: NW 8-12 kt this afternoon. Then variable 2-7 kt overnight.

BOI WATCHES/WARNINGS/ADVISORIES

ID...Air Quality Alert until 2 PM MDT Tuesday for IDZ011>015-028- 029-033. OR...Air Quality Alert until 11 AM PDT Monday for ORZ062.