511
FXUS65 KBOI 290604
AFDBOI

Area Forecast Discussion
National Weather Service Boise ID
1204 AM MDT Tue Sep 29 2026

.UPDATE...Updated aviation discussion.

&&

.KEY MESSAGES...
- Breezy northwest winds in the Snake Plain each afternoon
  through Wednesday.

- Fair skies and warmer temperatures through this weekend.

&&

.SHORT TERM /Through Wednesday Night/...
Issued 157 PM MDT MON SEP 28 2026
As a trough moves east, high pressure builds to the south of our
forecast area. Zonal flow will cap off the high pressure,
leading to a moderated warming trend up to about 5 degrees above
normal in the short term. Dry/fair weather is expected through
the period, as moisture in the flow is positioned along the
Canada-US border. West to northwest surface winds will become
breezy each afternoon in the Snake Plain, especially between
Boise and Twin Falls. The breezy 20-30 mph peak wind gusts occur
in an area where forecast minimum relative humidities are around
15-20%, creating elevated fire weather though in a very
localized portion of the high desert. Surface winds begin to
taper off heading into the long term forecast.

&&

.LONG TERM /Thursday through Monday/...
Issued 157 PM MDT MON SEP 28 2026
The area will remain under a flattened ridge north of a massive
Pacific high slowly building into the Great Basin region. This
continuous ridging pattern will favor clear skies, dry conditions,
and the return of warmer than normal temperatures Thursday through
Friday. A weak shortwave trough passing north of our area late
Friday may bring in some high cloud coverage, possibly moderating
the daytime temperatures on Saturday. Otherwise, broad Pacific
ridging will dominate the region Sunday through early next week,
continuing a much warmer and drier than normal pattern in the
extended outlook.

&&

.AVIATION /06Z Tuesday through Wednesday/...
Issued 1158 PM MDT MON SEP 28 2026

VFR. Surface winds: variable up to 12 kt, then W to NW 5-12 kt
during the afternoon. Afternoon gusts around 20 kt between KBOI-
KJER. Winds aloft at 10kft MSL: NW 10-20 kt.

KBOI...VFR. Surface winds: SE-SW 3-7 kt overnight, then NW 7-12
kt with gusts around 20 kt this afternoon.

&&

.BOI WATCHES/WARNINGS/ADVISORIES...
ID...None.

OR...None.

&&

$$

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AVIATION.....SH
SHORT TERM...JM
LONG TERM....JY