textproduct: Boise

UPDATE

Updated aviation discussion.

KEY MESSAGES

- Temperatures continuing 5 to 10 degrees above normal through Thursday.

- Slight chance of thunderstorms Wednesday into Thursday morning across eastern OR and southwest ID.

- Pattern change to cooler and unsettled beginning Friday as a trough arrives from the Gulf of Alaska.

- Temperatures around 15 to 20 degrees below normal Saturday and Sunday.

- Significant precipitation possible Friday through Sunday.

SHORT TERM /Through Friday Night/

Issued 408 AM MDT WED JUN 24 2026 Temperatures will remain around 5 to 10 degrees above normal through Thursday. A shortwave moves across the Pacific NW late this afternoon, with increasing high clouds and isolated showers and thunderstorms in eastern OR, and along the NV border in ID this afternoon and evening. The system will move over Idaho overnight, bringing a chance of showers and slight chance of thunderstorms overnight into Thursday morning. Clouds clear out midday Thursday before increasing clouds late from the next system arriving from the Gulf of Alaska. A cold front moves through southeast OR and southwest ID on late Thursday evening into Friday morning. It will take a while for conditions to moisten up in the low levels, as showers increase across the area and become widespread in coverage. As the main cold front moves through on Friday, partial clearing behind the front will lead to unstable conditions with scattered showers and thunderstorms during the afternoon and evening on Friday. Temperatures on Friday lower to around 10 degrees below normal.

LONG TERM /Saturday through Wednesday/

Issued 408 AM MDT WED JUN 24 2026 Cool and showery conditions continue on Saturday and Sunday with a slight chance of thunderstorms as the trough slowly moves overhead. Wetting rains possible Saturday and Sunday with temperatures around 15-20 degrees below normal. Significant precipitation possible with this system, depending on where the track of the system goes. As it stands right now, precipitation amounts of up to 1 to 1.25 inch possible over the central ID mountains, with lesser amounts in eastern OR, where less than 0.25 inch expected. Light snow possible on the peaks above 7000 feet Sunday morning. Conditions dry out with breezy conditions on Monday and Tuesday as the system moves northeast into Manitoba. This system will keep temperatures below normal under cool northwest flow aloft.

AVIATION /18Z Wednesday through Thursday/

Issued 1158 AM MDT WED JUN 24 2026 VFR with scattered mid-high clouds. High density altitude this afternoon from heat. Isolated showers/thunderstorms developing this afternoon in eastern OR and southwest ID near the NV border. Thunder capable of erratic outflows to 40 kt. Surface winds: W-NW 10-20 kt this afternoon, gusts up to 30kt near KONO and KBKE this evening through late night. Winds aloft at 10kft MSL: W-SW 5-15 kt.

KBOI...VFR with FEW-SCT high clouds. High density altitude this afternoon from heat. Isolated showers and a slight chance (10-15%) of thunderstorms late tonight through Thursday morning. Surface winds: NW 5-10kt this afternoon with gusts up to 20 kt from around 20Z to Thu/02Z.

BOI WATCHES/WARNINGS/ADVISORIES

ID...None.

OR...None.