081
FXUS65 KBOI 082007
AFDBOI

Area Forecast Discussion
National Weather Service Boise ID
207 PM MDT Wed Oct 8 2025

.SHORT TERM...Tonight through Friday night...Unseasonably warm
and dry conditions will dominate through the first half of
Friday, with highs running 10 to 12 degrees above normal and
peaking in the low 80s on Thursday. This warming trend is fueled
by strong southwesterly flow aloft as an upper- level trough
gradually moves south along the Pacific Northwest coast. As the
system deepens into a closed low off the Oregon coast, a dry
slot will form over southeast Oregon and southwest Idaho for
much of Friday. While this dry influence keeps early fall-like
conditions in place, instability along the edge of the
moisturedrawn from the southwestern U.S.will allow for a
slight chance of thunderstorms (1020%) across south-central
Idaho during the Friday afternoon and evening hours.

The greater coverage of precipitation begins late Friday
evening with the arrival of the cold front. The chance of
showers will increase to 2040 percent in the valleys. However,
pronounced 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 6080 percent.

.LONG TERM...Saturday through Wednesday... Unsettled conditions will
prevail throughout the long term. Deterministic and ensemble models
are in good agreement of the closed-low off the coast of California
coming onshore Saturday. Steering flow from the trough should keep
the remnant moisture from what is now Hurricane Priscilla and
Tropical Storm Octave to our south and east. None the less, this
trough will bring with it cooler temperatures and showers across our
area. Chances of precipitation Saturday into Sunday morning will be
60-80% across higher terrain and 40% in valley locations.
Precipitation chances lower slightly Sunday afternoon into early
Monday, as brief shortwave ridging builds in. Model ensembles are
coming into agreement on a reinforcing shot of energy propagating
through the northwest flow aloft and closing off into a low just
west of our area. As a result, precipitation chances will remain
elevated Monday through Wednesday. Both the GFS and Euro ensembles
have been consistent showing measurable precipitation throughout the
long-term, a sign of the unsettled conditions to come.

The precipitation won`t just be in the form of rain throughout the
long term. Snow levels will lower to 5-6kft by Saturday night/Sunday
morning before hovering around 6-7kft beyond Sunday. This will allow
snow to fall over higher terrain. Any accumulations won`t stick
around for too long as our area gets into the warm sector of the
second system, warming daytime highs to above freezing. Temperatures
will be cool to around 10 degrees below normal by Sunday, following
a cold frontal passage from the first system, generally
hovering there through Wednesday. Although there will be a brief
period of warming Monday as we get into the warm sector of the
second system.

&&

AVIATION...VFR. LLWS developing early Thu morning, especially near
KJER. Surface winds: E-SE 5-15 kt with gusts up to 25 kt. Winds
aloft at 10kft MSL: S-SW 15-25 kt.

KBOI...VFR. LLWS possible early Thu morning. Surface winds: SE 10-15
kt, gusting up to 25 kt until Thu/00z.

&&

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

&&

$$

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