textproduct: Boise

UPDATE

Updated aviation discussion.

KEY MESSAGES

- Near to slightly above normal temperatures through Friday.

- A weak cold front brings a slight chance of showers to Baker County and the West Central Mountains of Idaho on Sunday.

- Significantly above normal temperatures develops next week, peaking Wednesday around 15 degrees above normal with potential record highs.

SHORT TERM /Through Saturday Night/

Issued 208 PM MST THU NOV 5 2026 Quiet and dry weather is expected across southeast Oregon and southwest Idaho through Saturday night. An upper level ridge builds into the Intermountain West behind departing weak northwest flow, allowing heights and thickness values to steadily rise. Dry air will maintain mostly clear to partly cloudy skies with light surface winds, though some overnight valley inversions and patchy early morning fog remain possible in sheltered basins. High temperatures will trend upward each afternoon, climbing several degrees above normal for early November. Lows will remain seasonal to slightly mild. No significant weather hazards or travel impacts are anticipated through the period.

LONG TERM /Sunday through Thursday/

Issued 208 PM MST THU NOV 5 2026 A weak shortwave and accompanying cold front will track across the Pacific Northwest on Sunday. Moisture and dynamics remain quite limited with this boundary, confining a slight chance of light showers mainly to northern Baker County and the West Central Mountains of Idaho. The remainder of southwest Idaho and southeast Oregon will stay dry with little more than passing mid and high clouds.

Behind this system, the synoptic pattern amplifies substantially heading into early next week. A deep upper level trough establishes itself off the Pacific Coast, pumping strong south- southwesterly flow and anomalous warmth northward into the Great Basin and northern Intermountain region. Temperatures will climb rapidly from Monday onward. By Wednesday, high temperatures are projected to peak in the mid to upper 60s for lower elevation valleys, which is roughly 15 degrees above seasonal normals. Several locations, including the Treasure Valley, could approach or exceed daily record highs. Dry and tranquil conditions will persist across the forecast area through mid-week under this strong ridge before model guidance begins to hint at unsettled weather approaching late in the week as the offshore trough edges eastward.

AVIATION /00Z Friday through Saturday/

Issued 410 PM MST THU NOV 5 2026 Mostly VFR with some mountain obscuration and broken cloud cover. Skies clear tonight and fog/low stratus is again possible in KBKE/KBNO/KMYL, with a low chance near KEUL/KONO as SE winds should work against fog. Surface winds: W-NW 5-10 kt becoming SE tonight. Winds aloft at 10kft MSL: NW 5-15 kt.

KBOI...VFR. Surface winds: NW 5-10 kt and SE 4-8 kt by late evening.

Weekend Outlook...Mainly VFR with mid to high clouds on Friday and Sunday. Isolated showers across the north on Sunday. Patchy fog each night and early morning across sheltered basins. Surface winds variable less than 10 kt on Friday, then E-S 5-15 kt with gusts to 20-30 kt Saturday and Sunday.

BOI WATCHES/WARNINGS/ADVISORIES

ID...None.

OR...None.