634
FXUS66 KOTX 031059
AFDOTX

Area Forecast Discussion
National Weather Service Spokane WA
359 AM PDT Wed Sep 3 2025

.KEY MESSAGES...

- Hot temperatures this week (especially through Wednesday and
  Thursday), locally near 100, with major to locally extreme
  HeatRisk. Record high temperatures for September possible for
  multiple locations.

- Breezy northeast winds for Idaho and portions of the Columbia
  Basin Thursday evening into Friday.

- Unsettled weather returning to the region over the weekend
  and into next week.

&&

.SYNOPSIS...
High temperatures will climb into the upper 90s to near 100
degrees through Friday. Unsettled weather returns to the region
over the weekend and into next week.

&&

.DISCUSSION...
HOT WEATHER WITH WIDESPREAD MAJOR HEATRISK...

Today: A strong upper-level ridge will continue to deliver record
breaking heat to the Inland NW. High temperatures will continue
to soar into the upper 90s to lower 100s and only cool into the
60s to 70s. The one caveat to high temperatures will be
increasing haze and wildfire smoke. Wildfires in the Cascades,
Northeastern WA, and North Idaho have become very active over
the last 24 hours and producing greater amounts of smoke. There
will be a slight increase in northwest transport winds today and
smoke models suggest more smoke to drift into the Basin vs the
last few days. Meanwhile, fires may continue to experience hot,
dry, and unstable weather conditions with potential to remain
very activity so not thinking conditions will improve any time
soon. Those sensitive to smoke and air quality will need to
monitor conditions closely.

Thursday-Friday: We do see some changes coming later Thursday as
cooler air descends down the eastern flank of the ridge east of
the Rockies. This will increase easterly pressure gradients at
the surface and lead to breezy east to northeast winds. The
initial push will come into Idaho Thursday afternoon and evening
then fan out into the Basin overnight into Friday morning. The
push will be short lived and wane by Friday afternoon but bring
concerns to our active wildfires within the Idaho Panhandle and
eastern reaches of WA. The push will knock down temperatures a
few degrees mainly for eastern WA and North Idaho and deliver a
subtle increase in dryness levels. Central WA will not
experience much in the way of changes from this with valley
highs still near the century mark. For Central WA, the one thing
we are watching are waves pivoting counterclockwise across the
Oregon Cascades and brushing the WA Cascades. These will usher a
slight increase in midlevel moisture and a few hi-res models do
advertise isolated convection in the WA Cascades Thursday and
Friday afternoons. SREF has between a 10-30% chance for the
Cascade Crest and into the west slopes of the Cascades on
Thursday then 5% on Friday.

The weather pattern becomes a bit more uncertain and likely unsettled
going into the weekend and next week. Ensembles are coming into
better agreement of a trough slowly working its way to the
PacNW Coast and eventually coming inland by late week. As it
approaches the region, there are signals that smaller waves will
rotate into the region bringing a potential for waves of
showers and thunderstorms. Still too early to have much
confidence in the strength of the convection, amount of
precipitation and lightning, and exact impacts. However, anytime
we are breaking down heat, I would anticipate the potential for
dry lightning and gusty winds with an evolution to wetter storm
systems. NBM potential range of temperatures have shrunk toward
10 degrees and definitely show a cooling trend commences from
Sunday into next week which is supported by the 100 member
clustering of the upper-level patterns showing a transition
toward the aforementioned trough. My concern will be the initial
waves pivoting inland roughly from Saturday through Monday. Do
these take a negative tilt and bring stronger storms, gusty
winds, and abundant lightning or come through with less of a
negative tilt and resultant lower impacts. We will be monitoring
the evolution of this pattern change very closely in the coming
days. /sb

&&

.AVIATION...
12Z TAFS: Some airfields in the Cascades, northern Washington,
and northern Idaho may experience periods of MVFR conditions
from smoke from local fires. Otherwise, light winds and VFR
conditions will prevail through the 24 hr TAF period.

FORECAST CONFIDENCE AND/OR ALTERNATE SCENARIOS:
Low confidence in MVFR or worse conditions from smoke
developing at any TAF sites.

-----------------------

Confidence descriptors:
Low - Less than a 30 percent chance
Moderate - 30 to 70 percent chance
High - Greater than a 70 percent chance

For additional probabilistic information for NWS Spokane
airports, please refer to the Aviation Dashboard on our webpage:
https:/weather.gov/otx/avndashboard

&&

.Preliminary Point Temps/PoPs...
Spokane       101  65  96  62  92  62 /   0   0   0   0   0   0
Coeur d`Alene  99  64  94  61  91  61 /   0   0   0   0   0   0
Pullman        98  62  94  58  91  59 /   0   0   0   0   0  10
Lewiston      103  70 100  67  98  68 /   0   0   0   0   0  10
Colville      101  55  96  51  92  53 /   0   0   0   0   0   0
Sandpoint      96  58  89  54  88  56 /   0   0   0   0   0   0
Kellogg        97  67  91  61  88  63 /   0   0   0   0   0   0
Moses Lake    103  64  99  65  95  64 /   0   0   0   0   0  10
Wenatchee     103  74  99  70  94  72 /   0   0   0   0   0  10
Omak          104  69 100  67  96  66 /   0   0   0   0   0  10

&&

.OTX WATCHES/WARNINGS/ADVISORIES...
WA...Heat Advisory until 8 PM PDT Thursday for Central Chelan
     County-Northeast Blue Mountains-Northeast Mountains-
     Okanogan Highlands-Spokane Area-Upper Columbia Basin-
     Washington Palouse-Waterville Plateau-Western Chelan
     County-Western Okanogan County.
     Extreme Heat Warning until 8 PM PDT Thursday for Lower
     Garfield and Asotin Counties-Moses Lake Area-Okanogan
     Valley-Wenatchee Area.
     Air Quality Alert until 5 PM PDT Friday for Moses Lake Area-
     Northeast Mountains-Spokane Area-Upper Columbia Basin-
     Waterville Plateau.
     Red Flag Warning from noon today to 9 PM PDT Thursday for
     Colville Reservation (Zone 702)-Foothills of Northeast
     Washington (Zone 701)-Okanogan Highlands and Kettle
     Mountains (Zone 699)-Selkirk Mountains of Northeast
     Washington (Zone 700).
     Red Flag Warning until 9 PM PDT Thursday for East Washington
     Central Cascades (Zone 696).
ID...Heat Advisory until 8 PM PDT Thursday for Central Panhandle
     Mountains-Coeur d`Alene Area-Idaho Palouse-Lewis and
     Southern Nez Perce Counties-Northern Panhandle.
     Extreme Heat Warning until 8 PM PDT Thursday for Lewiston Area.

&&

$$