textproduct: Boise

UPDATE

Updated aviation discussion.

KEY MESSAGES

- Very hot temperatures through Saturday.

- Smoke persisting through at least Sunday.

- Breezy afternoon winds Friday through Sunday.

- Slight chance of thunderstorms along the ID/NV Saturday and Sunday as high-level monsoon moisture advances northward.

SHORT TERM /Through Sunday Night/

Issued 110 AM MDT FRI AUG 7 2026 Hot and Smoky conditions will persist through this weekend, with an upper level high over the Great Basin. This afternoon will be the warmest day of the period, with temperatures in the Snake Plain warming to around 100 degrees (with localized areas of up to 105 degrees). Across the high desert and mountain valleys, temperatures will reach the mid to upper 90s. Saturday afternoon will feature similar temperatures, although generally a couple degrees cooler than today. While the afternoons will be hot, dry conditions will allow for good radiational cooling overnight. This will allow for lower elevation overnight lows generally in the 60s. A week upper level disturbance will aid in weakening the ridge come late Saturday into Sunday. This feature will bring in breezy conditions this weekend with more cooling come Sunday. The strongest gusts will come Saturday afternoon, with gusts to around 25 mph, primarily in the southern zones and typical breezy spots of the Snake Plain.

Some mid-level monsoonal moisture will begin to work it's way around the Great Basin high today and through the weekend. While this moisture will stay south of our area this afternoon, it will continue to creep north to the ID/NV border come Saturday and Sunday. While the moisture reaching our area will be rather marginal (PWAT values in the 70-75th percentile of climatology as the LREF sees it), it could allow for the development of high-based showers/thunderstorms near the ID/NV border come Saturday/Sunday afternoons. While chances are low (generally under 15%), with dry low-levels even virga showers could produce gusty and erratic winds.

LONG TERM /Monday through Friday/

Issued 110 AM MDT FRI AUG 7 2026 Following the passage of the weak disturbance in the short-term, flow aloft will take on a zonal posture with the high pressure aloft shifting to our south. Temperatures on Monday will cool to near normal, where they will hover throughout the rest of the period. Each afternoon will also feature breezy conditions. Uncertainty in the pattern evolution begins to increase come mid-week this coming week. The LREF grand ensemble indicates troughing developing over the Pacific Northwest come midweek and beyond, with another push of monsoonal moisture making it's way north. For now the long-term forecast is dry, but the monsoonal push will be monitored for the potential need to introduce precip and thunder chances as the pattern evolution comes into better focus.

AVIATION /12Z Friday through Saturday/

Issued 417 AM MDT FRI AUG 7 2026

Areas of MVFR visibility and mtn obscuration due to wildfire smoke. Most notable near KBKE/KBNO/KONO. High density altitude due to heat each afternoon through the weekend. Surface winds: Variable up to 10 kt this morning, then W-NW 5-15 kt Fri/PM. Winds aloft at 10kft MSL: W-SW 5-15 kt.

KBOI...Smoke from nearby wildfires impacting visibility throughout the day with MVFR conditions possible this morning and overnight Friday. Foothills obscured in smoke. Surface winds: SE 3-7 kt this morning, then NW 7-12 kt.

Weekend Outlook...Areas of MVFR visibility and local mountain obscuration due to wildfire smoke, otherwise VFR. High density altitude each afternoon due to hot temperatures. A 15% chance of afternoon thunderstorms along ID/NV border Friday through Sunday. Surface winds: W-NW 7-12 kt with gusts 15 to 20 kt during the afternoons/early evenings, otherwise variable less than 10 kt.

BOI WATCHES/WARNINGS/ADVISORIES

ID...Air Quality Alert until 2 PM MDT this afternoon for IDZ011>015- 028-029-033. Heat Advisory until 9 PM MDT Saturday for IDZ012-014>016-029- 030-033. OR...Heat Advisory until 9 PM MDT /8 PM PDT/ Saturday for ORZ061>064. Air Quality Alert until 1 PM MDT /noon PDT/ this afternoon for ORZ061>064.