184
FXUS65 KBOI 092010
AFDBOI

Area Forecast Discussion
National Weather Service Boise ID
210 PM MDT Thu Oct 9 2025

.SHORT TERM...Tonight through Saturday night...Unseasonably
warm and dry weather will continue through Friday. Highs will
run 10 to 15 degrees above normal, reaching the low to mid-80s
in the valleys today and Friday. This warming is driven by
strengthening southwest flow aloft ahead of an upper-level
trough moving south along the Pacific Northwest coast, which
will also bring increased southerly surface winds with gusts up
to 40 MPH.

By Friday, the trough will deepen into a closed low near the
Oregon coast, pulling a dry slot over southeast Oregon and
southwest Idaho and maintaining warm and dry conditions for much
of the day. The cold front remains the main focus, with its
passage expected Friday evening into early Saturday morning
across eastern Oregon and southwest Idaho. Ahead of the front,
the combination of increased tropical moisture from the
southwestern U.S. and rising instability will be the catalyst
for isolated evening thunderstorms across southern Idaho. The
greater coverage of precipitation will begin late Friday evening
with the arrival of the cold front. The chance of showers will
increase to 1530 percent in the valleys. However, strong
southwest flow behind the front will favor upslope regions, with
the west-central Idaho and Boise Mountains expected to receive
the brunt of the moisture, where shower chances climb to 5070
percent.

The trough moves inland by Saturday, maintaining scattered
showers of 2040 percent in the valleys and 5080 percent in the
mountains. Temperatures will drop to about 47 degrees below
normal Saturday. Winds will become west-northwest behind the
front on Saturday afternoon with gusts of 20 to 30 mph.

.LONG TERM...Sunday through Thursday...Cooler temps and unsettled
conditions will be the name of the game throughout the long term
period. Early Sunday, the core of the trough that has sat west of
our area will pass over head. This is as it begins filling in an
embedding itself back into the main flow aloft. As this passes
overhead, snow levels will drop to 5-7kft Sunday. With these snow
levels, higher elevations will likely see precipitation in the form
of wintery mix/snow, especially early Sunday morning. Throughout the
day Sunday, locations above 6500 feet have a 40-80% chance of seeing
greater than 2 inches of snow (highest probabilities across higher
elevations in northeastern Valley county). By Monday, Ensembles
remain in good agreement of another trough digging down from British
Columbia and closing off into a low over California. This will put
our area in the warm sector; Thus, any snow accumulations over the
weekend will likely not stick around for too long. As this unfolds
on Monday, precipitation chances will taper off in lower elevations
and lower to  While uncertainty remains beyond Monday, This pattern
would favor below normal temperatures and periodic chances of
precipitation. Precipitation chances Tuesday and beyond will be 15-
40% across the majority of our area (higher chances found across
higher terrain).

&&

.AVIATION...VFR. LLWS redeveloping late Thu night/early Fri
morning. Showers developing over the ID W-central mountains
overnight tonight. Surface winds: S-E 10-20 kt. Winds aloft at 10kft
MSL: S-SE 20-30 kt.

KBOI...VFR. LLWS developing late Thu night/early Fri morning.
Surface winds: SE 8-12 kt with gusts to 18 kt this
afternoon.

Weekend Outlook...Areas of mountain obscuration Sat morning with
showers and isolated thunderstorms. Showers continue into Sunday
with snow levels 5-7kft MSL and mountains obscured. Breezy
conditions Saturday and Sunday afternoon with W-NW gusts of
20-30kt.

&&

.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...JDS
LONG TERM....NF
AVIATION.....NF