textproduct: Boise

UPDATE

Updated aviation discussion.

KEY MESSAGES

- Isolated showers and thunderstorms through this evening.

- Isolated thunderstorms confined to the central Idaho mountains and near the Idaho-Nevada border Wednesday through Friday, before drying out this weekend.

- Steady warming trend throughout the week with dry conditions and temperatures near normal on the 4th of July.

SHORT TERM /Through Thursday Night/

Issued ISSUED BY NATIONAL WEATHER SERVICE POCATELLO ID A weak shortwave trough traversing the area has already initiated showers across southeast Oregon early this afternoon. Temperatures in the mid 70s across the lower terrain with above normal moisture available should allow for further destabilization across southwest Idaho later this afternoon for isolated thunderstorm development. Though surface dew points remain above normal for this time of year, high-res models suggest the stronger storms could produce gusty outflow winds up to 40 mph. A few storms could make it into the Snake Plain early this evening, though the majority of activity is expected to remain over the higher terrain. Convective activity is forecast to diminish rapidly after sunset as daytime heating is lost, leading to clearing skies tonight.

On Wednesday, the shortwave departs to the east while a weak ridge builds across the region. Mostly sunny conditions will prevail, though a slight chance (10 to 20 percent) of isolated thunderstorms in the afternoon exists near the Nevada border and across the central Idaho mountains where the greatest axis of moisture persists. This threat will continue into Thursday with no significant change in the pattern aloft. Afternoon highs will trend warmer each day, reaching the mid 80s in the lower valleys on Thursday.

LONG TERM /Friday through Tuesday/

Issued ISSUED BY NATIONAL WEATHER SERVICE POCATELLO ID The last bit of shortwave troughing aloft will move overhead then east of the area on Friday, promoting isolated showers and thunderstorms over the higher terrain of Idaho. Beginning over the weekend, cluster analysis shows the Four Corners upper-level ridge dominating the synoptic pattern, with the primary question being the amplitudeness (intensity). Regardless of the intensity, a persistent and steady warming trend will define this weekend into the beginning of next week. The current forecast for the 4th of July is warm and dry across the area. Southwesterly flow aloft returns Monday and Tuesday with an upper-level trough lurking in the Gulf of Alaska, returning isolated showers and thunderstorms to the higher terrain.

AVIATION /00Z Wednesday through Thursday/

Issued 449 PM MDT TUE JUN 30 2026 VFR. Isolated showers and thunderstorms through tonight, mainly over the ID W-Central mtns and near the ID/NV border. Thunderstorms capable of outflows to 30-35 kt. Isolated showers returning Wed/AM, mainly across SW-Idaho, with Isolated thunderstorms Wed/PM mainly over the ID W-Central mtns and near the ID/NV border. Surface winds: W-NW 8-12 kt this afternoon, then light and variable overnight. Winds aloft at 10kft MSL: W-SW 5-15 kt.

KBOI...VFR. Low chance (<15%) of rain showers through tonight. Then isolated showers Wed/AM, a 30% chance of showers with a 10% chance of lightning Wed/AM. Surface winds: NW 5-10 kt Tue/PM then light and variable overnight.

BOI WATCHES/WARNINGS/ADVISORIES

ID...None.

OR...None.