textproduct: Boise

KEY MESSAGES

- Strong cold front late Wednesday with widespread rain and snow (snow level 6500-7000 feet).

- A 20% chance of thunderstorms Wednesday afternoon in southeast Oregon and southwest Idaho.

- Windy and colder Thursday. Westerly gusts 40 to 50 mph in the Snake Plain.

SHORT TERM /Through Thursday Night/

The leading edge of PoPs has been trimmed to better match QPF as a strong cold front enters our CWA Wednesday. The front will reach Baker County early Wednesday morning and western Idaho Wednesday afternoon and bring valley rain and mountain snow to the region. Brief heavy rain and gusty winds will occur initially, then decrease behind the front late in the day.

Instability (100-250 J/kg CAPE) will support a 20% chance of thunderstorms near the cold front Wednesday afternoon and evening. Outflow gusts as strong as 45 mph may occur in the Treasure Valley and western Magic Valley. Showers will linger in the mountains through Thursday, with snow level lowering to 4000-4500 feet. Westerly wind gusts will increase to 40-50 mph in south-central Idaho Thursday afternoon, and a Wind Advisory is being considered.

LONG TERM /Friday through Tuesday/

The back end of a deepening trough will continue strong north- northwest flow over the region, continuing cooler than normal temperatures and gusty northwest winds Friday. A broad ridge will build inland from a large high pressure center off the Pacific coast this weekend, bringing a gradual warming trend and mostly clear conditions for the central and southern portions of the area. Sunday will be the warmest day of the extended period. Remnant upper moisture will keep a 20-40% chance of light precipitation over the northern-most parts of our area this weekend.

The polar jet stream across western Canada is forecast to dip southward into the northwest US Monday and Tuesday. Precipitation will increase as a cold front passes through, especially in the mountains due to orographic enhancement. Windy and colder weather will follow on Tuesday with snow level lowering to valley floors. However, by then moisture will be decreasing and little if any snow accumulation is expected in the valleys.

AVIATION /06Z Wednesday through Thursday/

Issued 515 PM MST TUE MAR 3 2026

VFR, except patchy fog over mountain valleys Wednesday early morning. After Wed/12Z, cold front with precipitation will move from NW to SE. Widespread low VFR to IFR developing in rain, and IFR-LIFR in mountain snow. Snow levels 5.5-6.5kft MSL Wed AM, lowering to 4.5-5.5kft by Wed PM. Lightning strikes possible Wed PM. Mtns becoming obscured with front. Surface winds: S-SE 5-15 kt, shifting to W-NW 10-25 kt with 25-45 kt gusts with frontal passage Wed. Winds aloft at 10kft MSL: SW 15-30 kt.

KBOI...VFR through Wed AM. Cold front with rain arriving between Wed/18Z-20Z. Rain becoming showery by Wed evening. Lightning strikes possible Wed PM. Periods of MVFR/IFR during heavier rain. Foothills obscured with precip. Surface winds: S-SE 5-15 kt, shifting to W-NW 10-20 kt with gusts 20-35 kt with front Wed afternoon.

BOI WATCHES/WARNINGS/ADVISORIES

ID...None. OR...None.