440
FXUS65 KBOI 030957
AFDBOI

Area Forecast Discussion
National Weather Service Boise ID
357 AM MDT Wed Sep 3 2025

.SHORT TERM...Today through Friday night...An upper level ridge
axis will remain oriented over eastern WA and Idaho today, with
a weak elongated system over northern CA and southern OR
extending into Arizona. This system will bring mostly cloudy
skies to southeast OR and isolated showers and thunderstorms
each afternoon into Friday. Gusty erratic outflow winds up to 45
mph possible this afternoon and Thursday afternoon. The upper
level ridge will slowly weaken into Friday, and temperatures
will cool a few degrees each day. The system will remain
stationary through the short term before lifting northward late
Friday. Temperatures remain around 8-13 degrees above normal
Today, before cooling 2-3 degrees on Thursday and Friday.

.LONG TERM...Saturday through Wednesday...The aforementioned
system will lift northward over the area on Saturday as a
shortwave moves inland off the Northern CA coast. Precipitable
water values reach the 80th percentile on Saturday, not nearly
as impressive as the last event on August 27th. The dynamics of
this trough will interact with the mid level moisture already
in place, with a 20-30 percent chance of thunderstorms across
eastern OR and far southwest ID, and a 10-20 percent chance of
thunderstorms north and east of the Snake Plain. Temperatures
cool to near normal on Saturday. Showers and thunderstorms
linger into Sunday and Monday as the trough remains just
offshore, with moisture lingering over the Rocky Mountains. The
trough is forecast to slowly move inland during the Tuesday-
Thursday timeframe with much cooler and unsettled conditions
possible. High temperatures have the potential to lower to 5-10
degrees below normal depending on where the center of the upper
level trough moves. If the center of the trough moves overhead,
high temperatures would be in the 50s and 60s with the first
taste of Fall this season.

&&

.AVIATION...VFR. Isolated showers/thunderstorms in SE Oregon,
capable of 30-40 kt gusts from downdrafts. Smoke layers.
Surface winds: variable 5-10kt becoming W-NW 5-15kt during the
afternoon, strongest in eastern OR. Winds aloft at 10kft MSL:
variable 5-15kt.

KBOI...VFR. Smoke layers. Surface winds: SE 5-10kt, becoming NW
5-10kt during the afternoon.

&&

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

&&

$$

www.weather.gov/Boise

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

SHORT TERM...KA
LONG TERM....KA
AVIATION.....KA