textproduct: Boise

UPDATE

Updated aviation discussion.

KEY MESSAGES

- Record high temperatures Wednesday through Friday with dry conditions.

- A pattern shift with a cold front on Saturday will bring cooler temperatures, mountain precipitation, and breezy westerly winds.

SHORT TERM /Through Friday Night/

Issued 313 AM MDT WED MAR 18 2026 A ridge of high pressure will continue to build over the region during the work week, bringing record high temperatures 15-25 degrees above normal. High temperatures in the Treasure Valley are anticipated to reach near or at 80F today through Friday. Temperatures overnight will plummet to the upper 30s/low 40s for most locations, except in areas where southeast winds remain elevated. Winds will generally be light through the period, with mostly clear skies.

LONG TERM /Saturday through Wednesday/

Issued 313 AM MDT WED MAR 18 2026 A pattern shift will come for the long term period with a cold frontal passage early Saturday. Temperatures will drop by 10-15 degrees with cloudy skies, increased precipitation chances over high terrain (30-50% chance), and breezy westerly winds. Zonal flow aloft will then help keep cooler temperatures over the region through Monday, albeit still about 5 degrees above normal. The ridge of high pressure then looks to rebuild briefly over the region on Tuesday and Wednesday. Model uncertainty remains high with regards to precipitation chances on Tuesday and Wednesday, primarily dependent on the evolution of a low over Western Canada. The best chance for precipitation (15-30% chance) looks to stay over southeast Oregon and high terrain in southwest Idaho through the end of the long term period.

AVIATION /18Z Wednesday through Thursday/

Issued 1111 AM MDT WED MAR 18 2026

VFR under mostly clear skies. Surface winds: light and variable, except up to 12 kt near KTWF/KJER. Winds aloft at 10kft MSL: W-SW 15-30 kt.

KBOI...VFR with light and variable surface winds.

BOI WATCHES/WARNINGS/ADVISORIES

ID...None.

OR...None.