textproduct: Boise

UPDATE

Updated aviation discussion.

KEY MESSAGES

- Warm, slightly above normal temperatures and dry conditions will continue through the middle of next week.

- Another cold front will move through the region midweek, bringing mountain showers and slightly cooler temperatures.

SHORT TERM /Through Tuesday Night/

Issued 218 PM MDT SUN MAR 22 2026 A ridge of high pressure will continue to build back over the region through Monday. This will keep a relatively cool zonal flow mostly to our north. While tonight will feel noticeably cooler with lows reaching near or below freezing in many locations, Monday highs will remain above seasonal normals.

By Tuesday, an atmospheric river associated with a low pressure system off the British Columbia coast will begin to transport moisture toward the Pacific Northwest. This system will attempt to push colder air and precipitation into southeast Oregon and southwest Idaho. However, the persistent ridge to our south will keep most of the moisture well north of the area. The higher terrain of Baker County and the West Central Mountains of Idaho have the best chance (30%) for any precipitation Tuesday. Snow levels will remain high, generally between 7000 and 8000 feet MSL, keeping any accumulations light and limited to the highest peaks. Expect unseasonable warmth to continue through the end of the period.

LONG TERM /Wednesday through Sunday/

Issued 218 PM MDT SUN MAR 22 2026 Warm weather will continue on Wednesday ahead of a cold front which is expected to arrive on Wednesday evening. The front will bring a 40 to 50 percent chance of precipitation late Wednesday through early Thursday across the northern half of our forecast area with snow levels briefly falling to around 5000 feet. It looks like the front will pass through without bringing any precipitation to the southern half of the forecast area. Breezy northwest winds behind the front will bring in colder air and temperatures will be be near seasonal normals on Thursday. Most forecast models indicate that an upper level ridge will rebuild over the western US again on Friday with the ridge strengthening into the weekend. Our forecast for southwestern Idaho and southeastern Oregon responds to that scenario and shows dry weather with a warming trend starting on Friday. Temperatures will rebound to around 10 degrees above normal on Friday and continue warming to about 15 degrees above normal by Saturday and Sunday.

AVIATION /00Z Monday through Tuesday/

Issued 534 PM MDT SUN MAR 22 2026 VFR conditions with SCT-BKN high clouds will continue tonight through Monday. Surface winds will be W-NW 5-10 kt this evening, becoming light and variable or SW-SE under 10 kt overnight through Monday afternoon. Winds aloft at 10 kft: SW 10 to 15 kts.

KBOI...VFR with NW winds 10 kt or less, becoming SE under 7 kt tonight through Monday morning.

BOI WATCHES/WARNINGS/ADVISORIES

ID...None.

OR...None.