textproduct: Boise

UPDATE

Updated aviation discussion.

KEY MESSAGES

- Unsettled conditions through early Tuesday, mainly on the Idaho side, with showers mainly over Magic Valley and Boise Mountains. - Snow levels near 5000-6500 ft MSL through Tuesday, with light snow showers continuing over higher terrain in southwest ID.

- Frost possible in the Snake Plain through Wednesday morning with temperatures 10 to 15 degrees below normal.

- Warm and dry conditions Wednesday through next weekend.

SHORT TERM /Through Wednesday Night/

Issued 344 AM MDT MON OCT 12 2026 centered over eastern OR will slowly dive south into the Great Basin today (Monday) through Tuesday, as its moisture load gradually weakens. Elevated precipitation chances will continue over the Magic Valley and the Boise Mountains this morning, before diminishing in spatial coverage in the afternoon through early Tuesday. Cooler temperatures 10 to 15 degrees below normal, and more moderate northwest wind breezes, will be in store today with the low passage. Snow levels in the 5000-6500 range over southwest ID will continue to favor light snow showers over high terrain areas through early Tuesday. Late Monday through early Tuesday, showers will be limited to the lower Magic Valley area near the NV border, as the system moves completely out of our area by late Tuesday. Overnight low temperatures near freezing and high surface moisture will bring morning frosts over most of the Snake Plain through Wednesday morning. A Pacific high pressure will quickly build into the area by late Tuesday, returning drier and warmer conditions through Wednesday. Temperatures will climb to near- seasonal normals Tuesday through Wednesday.

LONG TERM /Thursday through Monday/

Issued 344 AM MDT MON OCT 12 2026 of high pressure will continue to build into the western CONUS, keeping our area in a warm and dry trend Thursday through the weekend. Temperatures 5 to 10 degrees above normal remain likely Friday through Sunday. Mostly clear skies will be expected throughout the long-term, with some overnight/morning fog possible each day. Late Friday through early Saturday, a Pacific longwave trough will dig into the northwest coast and keep our area under a dry southwest flow. This flow will continue dry conditions and above normal temperatures over the weekend. Come Monday, a large upper low will slowly dive down from lower British Columbia but keep our area under a strong southwest flow. This pattern will likely continuing slightly above normal temperatures on Monday. There is long-term guidance on widespread precip associated with this low arriving by late Monday, but its timing and magnitude remain slightly uncertain for now.

AVIATION /12Z Monday through Tuesday/

Issued 537 AM MDT MON OCT 12 2026 Generally VFR. Wrap-around moisture will continue light rain/mtn snow this morning through tonight, mainly in s-central/central Idaho. Low-VFR/MVFR in low stratus or rain, IFR-LIFR in mtn snow. Mountains obscured in stratus/precip. Snow Levels: 5-7kft MSL for SW Idaho, 3.5-5kft MSL in E Oregon. Surface winds: NW-N 5-15 kt this morning through the evening. Winds aloft at 10kft MSL: variable 5-15 kt, then NW 5-15 kt Mon afternoon.

KBOI...VFR with SCT/BKN low-mid clouds. Surface winds: NW 5-12 kt this morning through evening.

BOI WATCHES/WARNINGS/ADVISORIES

ID...None.

OR...None.