632
FXUS65 KBOI 172005
AFDBOI

Area Forecast Discussion
National Weather Service Boise ID
205 PM MDT Mon Aug 17 2026

.KEY MESSAGES...
- Isolated showers and thunderstorms this afternoon over higher
  terrain, with gusty outflows up to 35 mph.

- Temperatures near or slightly above normal through mid-week,
  then heat amplifying for Thursday and Friday.

- Return of monsoon moisture Friday into the weekend will
  increase shower and thunderstorm chances once again.

&&

.SHORT TERM /Through Wednesday Night/...
A distinct line of very light showers is currently pushing north
over the Treasure Valley and Malheur County, with minimal
precipitation amounts observed as of 2pm MDT. Cloud cover will
continue to persist through the evening, with a weak shortwave
trough moving through the region this afternoon. This will
continue the 10-20% chance of showers and thunderstorms,
primarily over the central ID mountains and near the high
terrain over the NV-ID border. The primary hazards with any of
these thunderstorms will be gusty outflows up to 35 mph and
lightning. Thunderstorm potential is slightly lower than
previously forecast due to the widespread persistent cloud
clover this afternoon. Lingering moisture over eastern Valley
County tomorrow will keep a 5-10% chance of showers and
thunderstorms through the evening. High pressure will build
back in over the Intermountain West tomorrow through the end of
the short term period, bringing a steady warming and drying
trend with generally light winds. Smoke from Oregon/Washington
wildfires will filter into the region tomorrow, with the
thickest smoke over Baker County, OR.


&&

.LONG TERM /Thursday through Monday/...
The Four Corners upper-level ridge will continue to build Thursday
and Friday with the Pacific low pressure system slowly moving
towards the shore. Southwesterly flow aloft will transition to
increased southerly winds through much of the weekend. This pattern
will bring back summertime heat risk, with temperatures climbing to
near 100 degrees for lower elevations. Precipitation chances will
start isolated in the higher terrain of SW Idaho Thursday,
increasing to most higher elevations across SW Idaho and SE Oregon
Friday. Afternoon wind gusts will also become breezier late week
into the weekend. The upper-level trough will move onshore late
Friday into Saturday and quickly move NE through the Pacific NW and
Northern Rockies. Cooling temperatures to near-normal are forecast
Saturday and Sunday with this disturbance moving through.

&&

.AVIATION /18Z Monday through Tuesday/...
Issued 1120 AM MDT MON AUG 17 2026

VFR. Weak, isolated showers and thunderstorms this
afternoon/evening across NE Oregon and s-central/central Idaho,
including KTWF-KJER. Erratic outflows to around 35 kt possible.
Patchy surface smoke near KBKE/KBNO. Surface winds: variable up
to 10 kt, becoming SW-NW 5-15 kt this afternoon. Winds aloft at
10kft MSL: SW 5-15 kt, becoming W 5-15 by 00z/Tuesday.

KBOI...VFR. Weak, isolated showers and thunderstorms in SW
Idaho this PM, with a 10% chance of impacting KBOI. Possible
storm outflows around 20-30 kt in Treasure Valley. Surface
winds: variable or SE around 6 kt, shifting to NW-N 5-10 kt in
the afternoon.

&&

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

OR...None.

&&

$$

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SHORT TERM...SA
LONG TERM....CH
AVIATION.....CH