textproduct: Boise

UPDATE

Updated aviation discussion.

KEY MESSAGES

- Cool, breezy and unsettled weather through Friday. Higher mountains will see an additional 4 to 8 inches of snow.

- Frost or light freeze possible in agricultural valleys Friday and Saturday morning.

- Remaining unsettled through the weekend and into early next week. Temperatures will gradually warm towards normal.

SHORT TERM /Through Friday Night/

Issued 224 PM MDT WED APR 22 2026 The broad closed low over the Pac NW will lift northeast overnight, cutting off the steady precipitation that has helped break Boise's April rainfall record. While this low exits the region, energy dropping out of Canada will keep a 40-70% chance of showers across the mtns in Baker County and w-central Idaho through Friday. Snow levels drop to around 4kft MSL tonight, allowing for up to an inch of accumulation in mountain valleys. Higher elevations will see an additional 3 to 8 inches of additional snow, with most of it falling by midday Thursday. Southeast Oregon and the Snake Plain in SW Idaho will trend drier Thursday and Friday as shower development remains to the north and east. Thursday and Friday stay breezy, aided by northwest flow on the backside of the upper trough. Each afternoon will bring gusts of 20 to 30 mph with windier spots along the I-84 corridor and through the Camas Prairie seeing gusts of 30 to 45 mph. Friday and Saturday morning will bring the chance of a frost or light freeze in the Snake Plain. Lows will generally range between 32-36 on Friday morning, shifting colder (30-35) for Saturday.

LONG TERM /Saturday through Wednesday/

Issued 224 PM MDT WED APR 22 2026 A trough will extend into our region from a low center in central Canada through early next week. This will bring slightly below normal temperatures and precipitation chances (20-40%) to higher terrain through at least Monday. A push of moisture from an embedded shortwave to our south will bring elevated precipitation chances (40-60% chance) to the Nevada border through early next week. Accumulation looks to be minimal in any precipitation that forms. Snow levels will stay around 5000-6000 feet MSL through Tuesday, with higher elevations seeing light snow showers this weekend through Monday with lingering precipitation.

A high pressure system will move into British Columbia by Tuesday, starting a steady warming trend through the region and bringing temperatures back to normals for this time of year. Disagreement on the evolution of a coastal low pressure system to our south muddles the precipitation forecast on Tuesday through Wednesday. Current precipitation chances range from 10-30% over higher terrain and near the Nevada border on Tuesday and Wednesday.

AVIATION /06Z Thursday through Friday/

Issued 1150 PM MDT WED APR 22 2026

Scattered showers tapering off through the morning. Generally dry after Thu/12z. Patchy fog/low stratus overnight in sheltered mtn valleys. Low VFR-MVFR in rain showers, IFR-LIFR in snow and fog/low stratus. Scattered showers in the ID w-cnrtl mtns Thu/PM. Snow levels: 4-5.5 kft MSL Thu/AM, then 4.5-6.5 kft MSL Thu/PM. Surface winds: W-NW 5-15 kt, with gusts up to 30 kt near KTWF/KJER overnight. Then W-NW 5-15 with gusts to 20-25 kt Thu/PM, except 15-20 kt with gusts to 30-35kt near KTWF/JER. Winds aloft at 10kft MSL: W-NW 20-40 kt.

KBOI...Period of MVFR ceilings in rain showers, but conditions improving as showers end after Thu/07z. Ceilings rising and gradually dissipating through the morning. Surface winds: NW 8-12 kt overnight. Then NW 10-15 kt with gusts up to 25 kt in the afternoon.

BOI WATCHES/WARNINGS/ADVISORIES

ID...None.

OR...None.