textproduct: Boise

UPDATE

Updated aviation discussion and key messages.

KEY MESSAGES

- Moderate to heavy rain and mountain snow tonight, with minor accumulations of wet snow above 5000 ft.

- Strong cold front this evening in eastern Oregon and late tonight in western Idaho, with a narrow band of heavy showers and scattered thunderstorms along the front.

- Very windy with westerly gusts up to 45 mph in the Camas Prairie and Western Magic Valley Thursday.

SHORT TERM /Through Friday Night/

Issued 147 PM MDT WED APR 1 2026 Areas of moderate to heavy rain and mountain snow, and isolated thunderstorms, the rest of today and this evening ahead of a strong Pacific cold front moving inland. Hi-res models depict the cold front clearly as it passes through our CWA tonight, crossing the OR/ID border around midnight MDT, through the Boise metro 1-2 AM MDT Thursday, and Jerome/Twin Falls 4-5 AM Thursday. The front will bring an abrupt wind shift from southeast to west/northwest, with about an hour of heavy showers and scattered thunderstorms. Cold air behind the front will lower the snow level to valley floors, with rain likely changing to wet snow before ending in the Upper Treasure Valley, but accumulating around an inch in the Magic Valley. Overnight pcpn in the Snake Basin should total .25 to .50 inch, with heavier amounts in the Idaho mountains north of the Snake Basin. Pre-frontal rain may be heavy enough to bring rocks and mud down steep terrain onto roads like the Banks-Lowman Road. Persons should roads below steep terrain until pcpn decreases Thursday morning. Total pcpn (water equivalent) tonight through Thursday morning should be 0.75 to 1.50 inch in the mountains, including 3 to 6 inches of snow, but locally up to 15 inches on the higher peaks. Post-frontal west winds will increase to 45 mph in the Western Magic Valley and Camas Prairie Thursday morning and continue all day. A Wind Advisory is in effect there from 9 AM MDT Thursday to 9 PM MDT. Clearing skies and decreasing winds will allow cold nighttime low temps Thursday night and Friday night. Friday will be mostly sunny and about 10 degrees warmer than Thursday.

LONG TERM /Saturday through Wednesday/

Issued 147 PM MDT WED APR 1 2026 Guidance remains in good agreement that high pressure Saturday through Tuesday will bring a warming and drying trend. Temperatures 5-10 degrees above normal this weekend reach 10-15 degrees above normal by early next week. Afternoon highs in lower elevations will be in the lower 70s Monday and Tuesday. Light winds and clear skies persist in this period. Wednesday a weak upper level low moves through, bringing slightly cooler temperatures and wetter weather. Model solutions widely vary on the strength of the low, but even the strongest 10% of solutions bring only light rain showers and 20-30 mph gusts.

AVIATION /00Z Thursday through Friday/

Issued 559 PM MDT WED APR 1 2026

MVFR-IFR conditions with rain and snow showers through the evening. Thunderstorms with small hail/graupel, gusty outflows to 45 kt, and brief heavy rain are possible (30-50% chance) this evening as well. Overnight, a band of moderate rain/snowfall moves along the cold front through the area. Snow levels fall from 4-7kft MSL ahead of the front quickly to valley floors behind the front, meaning all elevations could see brief snow. Surface winds: SW 15-25 kt, tonight W-NW 20 kt with gusts to 30 kt along the front. Winds aloft at 10kft MSL: SW 25-40 kt.

KBOI...Low VFR as showers through the night. 10-20% chance of thunder in afternoon showers capable of producing small hail/graupel and locally gusty winds. A cold front passage tonight will bring W-NW 20-30 kt winds and moderate rain/snow showers.

BOI WATCHES/WARNINGS/ADVISORIES

ID...Wind Advisory from 9 AM to 9 PM MDT Thursday for IDZ016-028. OR...None.