textproduct: Boise

UPDATE

Updated aviation discussion.

KEY MESSAGES

- High pressure will bring above normal temperatures and dry conditions through the weekend and into early next week.

- Cooler temperatures and chances for precipitation return by the middle of next week.

SHORT TERM /Through Monday Night/

Issued 328 AM MDT SAT APR 4 2026 High pressure will build over the area through the period, bringing warmer and dry conditions. Highs today will warm around 10 degrees from yesterday, pushing temperatures to around 5 degrees above normal. Aside from patchy fog early this morning in mountain valleys, skies will be mostly clear. Winds will be light today. On Sunday, highs will climb another 4-8 degrees as the ridge axis moves overhead, with lower valleys reaching the lower 70s. High clouds will increase ahead of a weak trough, and a light east to southeast breeze will develop across the area. The warmest day is expected to be Monday, with highs increasing by another 2-4 degrees as the ridge begins to flatten. A weak system will bring a minimal (10-20%) chance of showers to northern areas late Monday with dry conditions elsewhere.

LONG TERM /Tuesday through Saturday/

Issued 328 AM MDT SAT APR 4 2026 A return to cooler, more active conditions will take place during the extended. Temperatures Tuesday will remain mild before a trough to our north brings around 10 degrees of cooling on Wednesday. Strong westerly flow aloft will bring breezy to gusty winds on Tuesday, especially across the higher terrain and southwest of the Snake Basin where gusts 30-45 mph are expected. Precipitation chances will increase Tuesday night as the trough approaches, reaching 30-50% across the area on Wednesday. Weak instability will support a 10-20% chance of thunderstorms near the Nevada border. Cooler air will also lower snow levels to around 4500-7000 feet MSL on Wednesday.

There is uncertainty with how the aforementioned trough will phase with a closed low located off the California coast. This interaction especially affects the Thursday through Saturday time period. A majority of ensembles depict a slower inland progression of the closed low, resulting in less troughing (drier and warmer) over our area during this time. However, a minority of ensembles indicate a faster inland progression of the closed low, allowing the trough overhead to deepen and slow its eastward progress. This would bring cooler temperatures with a higher potential for precipitation. For now, temperatures and snow levels are forecast to hold nearly steady from Wednesday. There will be a 10-30% chance of showers each day, except a 30-50% chance along our southern and eastern borders on Thursday.

AVIATION /12Z Saturday through Sunday/

Issued 541 AM MDT SAT APR 4 2026

Mainly VFR under clear skies. Patchy mountain valley fog this morning, including near KMYL. Surface winds: variable less than 10 kt. Winds aloft at 10kft MSL: NW 5-10 kt, becoming variable less than 10 kt by Sun/00Z.

KBOI...VFR. Surface winds SE 4-8 kt this morning, NW this afternoon, becoming SE again this evening.

Sunday Outlook...VFR, high clouds. Surface winds E-SE 5-15 kt.

BOI WATCHES/WARNINGS/ADVISORIES

ID...None.

OR...None.