938
FXUS66 KOTX 220451
AFDOTX

Area Forecast Discussion
National Weather Service Spokane WA
951 PM PDT Tue Jul 21 2026

.KEY MESSAGES...

- Very warm through Thursday with high temperatures in the upper
  90s to low 100s. Widespread moderate and major HeatRisk.

- Isolated thunderstorms Thursday morning and again in the
  afternoon may result in new fire starts and gusty outflow
  winds.

- Critical fire weather conditions Friday and Saturday
  afternoons due to low relative humidity and winds. Any new or
  ongoing wildfires will be capable of spreading rapidly.

&&

.SYNOPSIS...
Hot temperatures expected through Thursday. Smoke from local
wildfires will result in hazy skies and may keep high
temperatures cooler than currently forecasted. Increasing
moisture on Thursday may result in isolated thunderstorms
Thursday morning and again Thursday afternoon. Dry and breezy
winds Friday and Saturday will result in critical fire weather
conditions.

&&

.DISCUSSION...
Tonight through Thursday: A strong upper ridge centered over
the south central US combined with a low off the California
coast is providing a broad south to southwest flow across the
western US. The south to southwest flow will bring continued
warming of temperatures on Wednesday, with hot weather
persisting into Thursday. Continued light north to northeast
winds into Wednesday morning will allow for continued haze and
smoke to linger with the highest amounts across Central and
Northeast Washington given closer proximity to active wildfires.
There is not much in the way of wind given the influence of
high pressure through Thursday morning so not expecting any
major improvements to the smoke and haze situation through then.

The main weather feature of interest is the low off the
California coast which will send an increase in monsoonal
moisture up into the region along with a mid level short wave
passage on Thursday. Precipitable water values increase to
150-180 percent of normal while 700-500mb most unstable CAPE, as
well as surface based CAPE Thursday afternoon increase to as
much as 300-700 J/KG. The one missing ingredient is strong mid
level forcing. With the low still well off the coast and the
best upper level diffluence to the south across Oregon, the
forecast is leaning towards isolated coverage of thunderstorms,
with the best chances along the East Slopes of the Cascades into
the northern mountains, as well as over SE Washington into the
Central Panhandle where models indicate the two areas of best
instability. Yet would not rule out thunderstorms for any areas.
And even isolated thunderstorms are a concern given the hot and
dry weather preceding Thursday and dry fuels. Despite the high
moisture content in the atmosphere, the quick movement of storms
is expected to produce only light rain with storms, further
raising concerns for new fire starts.

Friday and Saturday: On Friday a large low from Alaska begins to
swing into British Columbia, which will act as a kicker to bring
the offshore low into the region as an open wave on Saturday.
This transition will bring dry and breezy winds on Friday,
followed by an additional wind increase for Saturday as a cold
front moves through. This will result in elevated to critical
fire weather conditions as west to southwest winds increase to
15 to 25 mph with gusts of 30-40 MPH. A cooling trend will
begin to help increase the relative humidity, but yet the
increasing winds will be a concern for any new or going fires.
No precipitation is expected as this system moves in, except for
the Cascade crest with most members from the ECMWF generating at
least light precipitation for Stevens Pass.

Sunday through Tuesday: Another low associated with the upper
level trough over British Columbia intensifies off the central
BC coast on Sunday, potentially sending another weak front
across the region on Monday. This will help keep our
temperatures in check with highs down in the 80s, which is near
to slightly cooler than normal. This should help bring some
moderation to the fire weather conditions for early next week.
Yet little to no precipitation is expected with this system
except for a chance of light showers along the Cascade crest. JW

&&

.AVIATION...
06Z TAFS: High pressure and light winds will allow smoke and
haze to continue across the Inland Northwest. Smoke may
intermittently reduce visibilities to MVFR across TAF sites.
Otherwise mid and high clouds will continue to stream into the
region from the southwest.

FORECAST CONFIDENCE AND/OR ALTERNATE SCENARIOS: Moderate
confidence in the visibility forecast at the 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:/www.weather.gov/otx/avndashboard

&&

.Preliminary Point Temps/PoPs...
Spokane        64  97  66  97  66  95 /   0   0   0  20   0   0
Coeur d`Alene  66  95  67  95  66  94 /   0   0   0  20   0   0
Pullman        59  91  61  91  58  91 /   0   0   0  10  10   0
Lewiston       69  98  70  99  68 100 /   0   0   0  20  20   0
Colville       59  97  62  96  61  95 /   0   0   0  20  10   0
Sandpoint      62  94  64  95  63  93 /   0   0   0  20  10   0
Kellogg        62  91  64  92  62  90 /   0   0   0  20  10   0
Moses Lake     65  99  68  98  64  98 /   0   0   0  20   0   0
Wenatchee      74 100  77  98  69  97 /   0   0  10  20   0   0
Omak           69 101  72  99  68  98 /   0   0   0  20  20   0

&&

.OTX WATCHES/WARNINGS/ADVISORIES...
WA...Heat Advisory until 9 PM PDT Thursday for Central Chelan
     County-Lower Garfield and Asotin Counties-Moses Lake Area-
     Northeast Blue Mountains-Northeast Mountains-Okanogan
     Highlands-Okanogan Valley-Spokane Area-Upper Columbia
     Basin-Washington Palouse-Waterville Plateau-Wenatchee
     Area-Western Chelan County-Western Okanogan County.
     Air Quality Alert until 9 AM PDT Wednesday for Moses Lake Area-
     Northeast Mountains-Okanogan Highlands-Okanogan Valley-
     Spokane Area-Upper Columbia Basin-Washington Palouse-
     Waterville Plateau-Western Okanogan County.
ID...Heat Advisory until 9 PM PDT Thursday for Coeur d`Alene Area-
     Lewis and Southern Nez Perce Counties-Lewiston Area-
     Northern Panhandle.

&&

$$