479
FXUS66 KOTX 230814
AFDOTX

Area Forecast Discussion
National Weather Service Spokane WA
114 AM PDT Thu Jul 23 2026

.KEY MESSAGES...

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

- Isolated to scattered thunderstorms Thursday morning and
  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 to scattered
thunderstorms through evening. Dry and breezy winds Friday and
especially Saturday will result in critical fire weather
conditions.

&&

.DISCUSSION...
Thursday through Saturday: A critical fire weather pattern will
commence as an offshore upper low slowly approaches the Pacific
Northwest. Elevated instability (50-100 J/KG of 700-300mb
MUCAPE) brings a 10-15% chance of isolated elevated showers and
thunderstorms thunderstorms Thursday morning. Instability
increases and transitions to surface based by the afternoon,
with models showing 1000-1500 J/kg of SBCAPE over the Cascades
and 500-1000 J/kg over northeast Washington, the Idaho
Panhandle, and far southeast Washington. CAMs are showing
stronger convection developing over the Cascades after 12PM,
shifting into the Okanogan Highlands and northeast Washington
through the afternoon. For southeast Washington, CAMs depict
convection firing around 1-2PM and moving to the northeast
through the afternoon and evening. Inverted-V soundings due to
hot and dry surface temperatures supports DCAPE above 1000 J/kg
Thursday afternoon, suggesting strong gusty outflow winds up
40-50 mph will likely accompany any showers or thunderstorms.
Increasing onshore flow into western Washington will strengthen
the cross-Cascade pressure gradient Thursday afternoon, with
general winds through the Cascade gaps around 10 to 15 mph with
gusts up 20 mph in the afternoon and evening.

By Friday into Saturday, an upper-level trough digs off the
Pacific Northwest coast from the Gulf of Alaska, pushing the
initial offshore low eastward, driving a dry cold front across
the region. Winds first increase on Friday as upper-level winds
begin to increase and mix down to the surface. Saturday
continues to be the most impactful period of the forecast as the
upper-level jet streak strengthens to 100-110 knots. Winds at
850mb and 700mb increase to 25-40 knots, which combined with a
+10mb PDX-GEG surface pressure gradient will support widespread
gusty winds with southwest wind gusts 25 to 45 mph. On Friday
the NBM indicates the best chances for critical wind and
relative humidity combo to occur across the east slopes of the
Cascades, Waterville Plateau, Okanogan Valley, and Western
Columbia Basin with sustained winds from the southwest 10 to 20
mph with gust 20 to 30 mph. Some cooling is expected on Saturday
(highs in the upper 80s to low 90s), raising the afternoon
relative humidity, with a 40-70% chance for sustained winds
greater than 15 mph and relative humidity below 20% across much
the Inland Northwest. Despite the wetter RHs, the winds are
expected to be stronger than Friday (20-60% chance for gusts
greater than 45 mph), negating any benefit of the cooler
temperatures. Any new or existing fires Saturday will be capable
of very rapid fire spread.

Sunday through Wednesday: Ensembles are in broad agreement for
the next upper-level trough to move onshore on Sunday, bringing
cooler conditions, continued breezy winds, and a chance for
light preciptiation along the Cascade crest. The Gulf of Alaska
will remain active through at least the middle of next week with
an amplified four corners high into the northern Rockies.
Onshore flow into western Washington will continue with breezy
and dry afternoon winds across the Inland Northwest. /vmt

&&

.AVIATION...
12Z TAFS: High pressure weakens as a low off the coast
approaches. Expect mostly VFR conditions. Regional wildfire
smoke will occasionally bring MVFR conditions. A shower and
thunderstorm threat will be found over the Cascades to north-
central WA this morning, becoming more likely this afternoon
into the evening before the risk shifts to the north WA and ID
Panhandle mountains and wanes overnight. Some passing t-storms
are possible at any TAF site, but the best chances will be near
KEAT 12-18Z and KLWS/KPUW this afternoon and evening (00Z to
06Z). Some gusty outflow winds near 30-40kts are possible with
any of these t-storms. Some afternoon wind gusts near 15-20kts
are possible at most TAF sites and other terminals.

FORECAST CONFIDENCE AND/OR ALTERNATE SCENARIOS: Moderate
confidence in the visibility forecast at the TAF sites. Low
confidence for any showers or thunderstorms at 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        99  67  96  63  91  58 /  20   0   0   0   0   0
Coeur d`Alene  98  66  95  64  91  59 /  20   0   0   0   0   0
Pullman        94  58  93  57  87  52 /  20  10   0   0   0   0
Lewiston      103  69 102  68  97  63 /  20  30   0   0   0   0
Colville       98  60  95  58  91  53 /  20  20   0   0   0   0
Sandpoint      96  63  93  60  91  57 /  20   0   0   0   0   0
Kellogg        94  61  92  61  87  56 /  20   0   0   0   0   0
Moses Lake    100  64  98  63  92  56 /  20   0   0   0   0   0
Wenatchee      99  69  98  68  89  62 /  20   0   0   0   0   0
Omak          101  68  99  64  92  58 /  30  10   0   0   0   0

&&

.OTX WATCHES/WARNINGS/ADVISORIES...
WA...Heat Advisory until 9 PM PDT this evening 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.
     Fire Weather Watch from Saturday morning through Saturday
     evening for Eastern Columbia Basin  -Palouse  -Spokane
     Area (Zone 708)-Foothills of Northeast Washington (Zone
     701)-Lower Palouse  -Snake River (Zone 709)-Okanogan
     Highlands and Kettle Mountains (Zone 699)-Selkirk
     Mountains of Northeast Washington (Zone 700).
     Air Quality Alert until 11 AM PDT Friday 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.
     Fire Weather Watch from Friday morning through Saturday
     evening for Colville Reservation (Zone 702)-Foothills of
     Central Washington Cascades (Zone 705)-Methow Valley
     (Zone 704)-Okanogan Valley (Zone 703)-Waterville Plateau
     (Zone 706)-Western Columbia Basin (Zone 707).
     Red Flag Warning from 1 PM this afternoon to 2 AM PDT Friday
     for Colville Reservation (Zone 702).
     Red Flag Warning until 2 AM PDT Friday for East Portion of
     North Cascades National Park/Lake Chelan National
     Recreation Area (Zone 697)-East Washington Central
     Cascades (Zone 696)-East Washington North Cascades (Zone
     698)-Foothills of Central Washington Cascades (Zone 705)-
     Methow Valley (Zone 704)-Okanogan Highlands and Kettle
     Mountains (Zone 699)-Okanogan Valley (Zone 703).
ID...Heat Advisory until 9 PM PDT this evening for Coeur d`Alene
     Area-Lewis and Southern Nez Perce Counties-Lewiston Area-
     Northern Panhandle.
     Fire Weather Watch from Saturday morning through Saturday
     evening for Northern and Central Idaho Panhandle (Zone
     101).

&&

$$