690
FXUS65 KBOI 102006
AFDBOI

Area Forecast Discussion
National Weather Service Boise ID
206 PM MDT Thu Sep 10 2026

.KEY MESSAGES...
- Cold front and gusty winds this evening, followed by breezy
  and slightly cooler weather Friday, then warmer again
  Saturday.

- Much stronger cold front late Saturday and Saturday night with
  wind gusts 35 to 45 mph in southern areas, and widespread
  showers and scattered thunderstorms in the north.

- Windy and much cooler Sunday, with showers continuing in the
  north.

- Warming and drying Monday and beyond.

&&

.SHORT TERM /Through Saturday Night/...
Mid to high level clouds are slowly building in over the area
from the south this afternoon, with isolated virga
showers/thunderstorms near the NV border through late this
evening. A dry cold front will sweep across the area later
today, bringing some elevated winds westerly winds this
afternoon through around sunset. Elevated wind breezes will
return Friday afternoon, while temperatures drop but remain
warmer than normal.

The major highlight of the short-term is the active pattern
arriving this weekend. Latest guidance slightly delayed the
Pacific upper low`s arrival to Saturday night. Ahead of this
low, our area will stay under a strong southwest flow, returning
warm temperatures up to 10 degrees above normal and sustaining
dry conditions throughout the daytime hours on Saturday. The
strong southwesterly winds with gusts up 45 mph, combined with
low RHs, will bring heightened fire weather concerns for the
southern areas near the ID/NV border.

The upper low will steer a strong cold front Saturday evening
through overnight, sustaining strong westerly winds and bringing
chances of precipitation over most of the area. The northern
half of our CWA will continue to see the bulk of the
precipitation, with the west central ID and east central OR
mountains seeing the highest likelihoods of heavy rain and
embedded scattered thunderstorms. There is considerable guidance
uncertainty over how much precipitation the lower valleys will
see. For now, the lower Treasure Valley area will generally see
total rainfall of around 0.01 to 0.05" and a 10-15% chance of
thunderstorms late Saturday through early Sunday.

&&

.LONG TERM /Sunday through Thursday/...
On Sunday, moderate to high precipitation chances will remain
over the northernmost mountain areas of our CWA, before tapering
off in the afternoon. Otherwise, a rapid cooling trend will be
in store for Sunday, with temperatures dropping well below
normal following the cold frontal passage. Snow levels will drop
down to the 7000-8000 ft range through Sunday morning, favoring
some light snowfall over high mountain peaks. By late Sunday,
our western zones should clear, and Sunday night will be cold
and mostly clear area-wide, except for valley fog early Monday
morning. Otherwise, Monday will continue to see temperatures
slightly below normal. A large ridge of high pressure will
rebuild over the northwest region and bring a warming and drying
trend through the rest of the week.

&&

.AVIATION /18Z Thursday through Friday/...
Issued 1054 AM MDT THU SEP 10 2026
VFR with SCT-BKN high clouds moving in from south. Isolated
thunderstorms/virga near NV border this afternoon/evening,
capable of gusty outflows 30-35 kt. Surface winds: SW-NW 10-15
kt, with gusts 20-25 kt in the Magic Valley, eastern OR, and
west-central ID mtns this afternoon after 20Z through sunset
tonight. Winds aloft at 10kft MSL:
W 25-30 kt.

KBOI...VFR with scattered high clouds. Surface winds: mostly
variable under 7 in the early afternoon, becoming NW 5-10 kt
after 20Z and through the evening.

Weekend Outlook...VFR with increasing SW surface winds in OR
Saturday afternoon. Strong Pacific cold front will arrive
Saturday evening, bringing widespread showers and scattered
thunderstorms mainly in Baker County OR and north of the Snake
Basin in ID. MVFR conditions and mountain obscuration in
precip. SW-W surface winds 20-30 kt with gusts to 40 kt
Saturday evening in southeast OR and southwest ID, with
strongest gusts near NV border. Showers, mountain valley fog,
and MVFR conditions continuing Sunday morning in west-central ID
before improving in the afternoon.

&&

.BOI WATCHES/WARNINGS/ADVISORIES...
ID...Fire Weather Watch from Saturday afternoon through Saturday
     evening for IDZ423-426.
OR...None.

&&

$$

www.weather.gov/Boise

Interact with us via social media:
www.facebook.com/NWSBoise
www.x.com/NWSBoise

SHORT TERM...JY
LONG TERM....JY
AVIATION.....JY