310
FXUS65 KBOI 140907
AFDBOI

Area Forecast Discussion
National Weather Service Boise ID
307 AM MDT Mon Sep 14 2026

.KEY MESSAGES...
- Breezy and cool today, with lingering mountain showers in
  northeast OR and central ID.

- Slight warming and drying trend Tuesday and Wednesday, with
  light winds.

- Another push of low pressure will bring precipitation to
  higher terrain and south central Idaho by the middle of this
  week.

&&

.SHORT TERM /Through Wednesday Night/...
Scattered low clouds and patchy valley fog will develop this
morning, primarily in high terrain, but clearing will occur by late
morning into the early afternoon. A deep low pressure system will
move northeast of the region today, keeping cool temperatures
and breezy westerly winds over the region with some lingering
mountain showers across northeast Oregon and central Idaho. A
longwave trough will keep slightly below normal temperatures
tomorrow, but southwest flow aloft will bring a slight warming
and drying trend by Wednesday. Another low pressure system will
dive into western Oregon late Wednesday, with southerly flow
allowing for some monsoonal moisture to move northward over
south central Idaho. This low will then track to the east over
our region on Thursday, bringing a slight chance of showers and
cooler temperatures. Isolated thunderstorms are possible as
well, especially Thursday afternoon. Light and primarily terrain
driven winds will dominate the short term period, with slightly
increasing southerly winds on Thursday.

&&

.LONG TERM /Thursday through Monday/...
Cool and unsettled conditions will continue on Friday, with showers
lingering over high terrain. Precipitation accumulations look to be
minimal and isolated to higher elevations in Baker County, OR and
the West Central Mountains. A short lived pattern shift will then
occur by the weekend. Model solutions have come into alignment over
the ridge of high pressure developing over the Intermountain West by
Saturday. This will bring above normal temperatures and dry
conditions through Monday, but another trough looks to move onshore
by the middle of next week.

&&

.AVIATION /06Z Monday through Tuesday/...
Issued 1155 PM MDT SUN SEP 13 2026

Generally VFR. Isolated showers across Baker County and the west-
central Idaho mountains creating mountain obscuration, then exiting
Monday morning. Patchy valley fog/mist Monday morning near KBKE,
KMYL, and KBNO. Surface winds: SW-NW 5-15 kt. Winds aloft at 10kft
MSL: W to NW 15-35 kt.

KBOI...VFR. Mid level clouds lowering to 3500-5000 ft AGL between
Mon/10Z-15Z, then clearing by the afternoon. Surface winds: NW
or variable 3-8 kt.

&&

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

OR...None.

&&

$$

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SHORT TERM...SA
LONG TERM....SA
AVIATION.....SH