textproduct: Boise

UPDATE

Updated aviation discussion.

KEY MESSAGES

- Widespread subfreezing temperatures tonight. - Drier and warmer conditions Friday through Sunday. Sunday will be 5-10 degrees above normal.

- Next chance of precipitation late Tuesday through Thursday from incoming Pacific low.

SHORT TERM /Through Sunday Night/

Issued 225 PM MDT THU APR 16 2026 Weak, scattered snow/graupel showers will taper off by tonight. Snow levels will stay at valley floors tonight through Friday afternoon. Winds are expected to weaken tonight, except elevated gusts up to 30 mph will continue over Magic Valley through around midnight.

Temperatures will drop down into the mid to upper 20s late tonight through Friday morning. As such, a freeze warning is in place tonight through Friday morning. Patchy fog is possible in sheltered mountain valleys. Otherwise, Friday will see some breezy northwest winds and much drier conditions, as a Pacific high pressure starts building into the region. Friday night through Saturday morning could see temperatures at or below freezing. Saturday will see clearer and calmer conditions with a slight warming trend to normal temperatures. Some elevated wind gusts are expected over East-Central OR and Upper Treasure Valley ID on Saturday.

LONG TERM /Monday through Friday/

Issued 225 PM MDT THU APR 16 2026 Mild and dry conditions will carry into early next week as a closed low digs off the West coast. Southerly flow will push temperatures to 10-15 degrees above normal for Sun-Tue, placing lower elevations in the mid-upper 70s and mtn valleys into the mid 60s. The forecast for Tuesday has trended drier and warmer due to slower progression of the Pacific closed low. Given recent model trends would expect forecast for Tuesday to continue leaning drier especially across SW Idaho zones. Model consensus is for the upper low to eject inland on Wednesday, bringing a 40-50% chance of showers in the valleys and 60- 80% chance in the mountains. Snow levels on Wednesday will range between 6-8kft MSL. A 20-40% chance of showers lingers on Thursday as models show the low kicking eastward. Temperatures will cool down to near normal for Wed/Thur.

AVIATION /06Z Friday through Saturday/

Issued 1225 AM MDT FRI APR 17 2026

Isolated snow showers this morning over the west-central mtns producing localized MVFR/IFR conditions. Local mtn valley fog in the morning. Otherwise, VFR with scattered cumulus over mtns. Surface winds: variable less than 10 kt, except SW-NW 10-20 kt in the Magic Valley. Winds aloft at 10kft MSL: NW 10-20 kt.

KBOI...VFR and mostly clear. Surface winds light and variable, becoming NW 5-10 kt this afternoon.

Weekend Outlook...VFR. Dry with periods of mid-high cloud cover. Local mtn valley fog Saturday morning. Surface winds S-SE 5-15 kt Saturday increasing to 10-20 kt with gusts 20-30 kt on Sunday. Strongest winds on Sunday in the Snake Plain east of KBOI. Variable up to 15 kt overnight Sat/Sun night.

BOI WATCHES/WARNINGS/ADVISORIES

ID...Freeze Warning until 10 AM MDT this morning for IDZ012-014-016. Freeze Warning from midnight tonight to 10 AM MDT Saturday for IDZ012-014-016. OR...Freeze Warning until 10 AM MDT /9 AM PDT/ this morning for ORZ064. Freeze Warning from midnight MDT /11 PM PDT/ tonight to 10 AM MDT /9 AM PDT/ Saturday for ORZ064.