856
FXUS65 KBOI 040306
AFDBOI

Area Forecast Discussion
National Weather Service Boise ID
906 PM MDT Wed Sep 3 2025

.DISCUSSION...
A few showers and thunderstorms remain across southeast Oregon
this evening, through activity has been minimal with the
shortwave passage well west of the region. A few storms produced
wind gusts up to 30 MPH, but no significant rainfall was
observed. Isolated showers and a few thunderstorms may persist
across mainly Harney County through Thursday evening.

An anomalously deep upper-level low over the Great Lakes will
suppress the ridge over the Western United States and strengthen
north to northwesterly flow, especially across the northern
Rockies. This pattern will transport high-level smoke from
several fires in Washington, northern Idaho, and southwestern
Canada into southwest Idaho Thursday and Friday.

&&

.AVIATION...VFR. Light smoke layers aloft through 20kft MSL. Virga
and isolated showers/thunderstorms continuing in SE OR and OR/NV
border this evening, with gusts 30-40 kt possible. Surface Winds: NW
or variable 5-10 kt through evening, becoming variable or SW 5-15 kt
overnight. Winds aloft at 10kft MSL: variable 5-10 kt.

KBOI...VFR. Light smoke layers aloft. Surface winds: NW 5-10 kt
through evening, becoming variable under 7 kt overnight.

&&

.PREV DISCUSSION...
SHORT TERM...Tonight through Friday night...Gradual day-to-day
cooling as the upper ridge weakens over the interior western US
while holding its position. Little change in weather features,
though, with a 10-20 percent chance of late-day showers and
thunderstorms continuing in eastern OR. Late Friday night a
Pacific short wave trough will swing inland, and with mid-level
monsoon moisture still present the chance of showers will
increase to 25 to 40 percent in eastern OR, and clouds will
increase in western ID.

LONG TERM...Saturday through Wednesday...Saturday will bring
the best chance of showers and thunderstorms (30-50 percent),
as the Pacific short wave trough moves through.  PoPs will
decrease from west to east Saturday night through Sunday as
the trough and monsoon moisture shift east. On Tuesday the
main Pacific upper low will come inland, and by Wednesday it
will be over our CWA with showers and much cooler temps.
Current forecast trends are conservative, but if today`s
models prove correct we will adjust them cooler and wetter,
i.e., highs temps in the 50s and 60s in the mountains and
60s to lower 70s in the valleys, and PoPs 50-80 percent.

&&

.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

DISCUSSION...JDS
AVIATION.....JY
SHORT TERM...LC
LONG TERM....LC