405
FXUS66 KOTX 152250
AFDOTX

Area Forecast Discussion
National Weather Service Spokane WA
350 PM PDT Sat Aug 15 2026

.KEY MESSAGES...

- Continued thunderstorm chances focused over mountain areas
  through the weekend.

- Temperatures warm back into the mid 80s to mid 90s by Sunday.

- Drier air returns early to mid next week.

&&

.SYNOPSIS...
A somewhat active pattern persists across the Inland Northwest
through the weekend and into early next week with continued
mountain thunderstorm chances each afternoon and evening.
Temperatures trend warmer through the weekend and into next week.
A drier airmass moves in by the middle of next week.

&&

.DISCUSSION...
Today and Sunday: Due to a low pressure system retrograding off the
PNW coast, the Inland Northwest will remain in southwesterly flow
for the next couple days. This will provide PWATs 100 to 150 percent
of normal (0.75 to 1 inch). Small disturbances passing through will
provide enough instability combined with daytime heating alongside
added moisture to result in chances for thunderstorms each afternoon
and evening this weekend. For this afternoon and evening, much of
the northern mountains and valleys, Cascades, Palouse, Spokane/CdA,
and ID Panhandle have a 10 to 20 percent chance of thunderstorms.
Today`s soundings indicate elevated PWATs 0.60 inches and above and
DCAPE values near 1000 J/kg, favoring gusty outflow winds near 40
mph. Additionally, lightning induced fire starts are possible. These
higher PWATs will keep fire concerns at elevated rather than
critical for all areas but the Lower Palouse and Snake River. For
this zone (709), a Red Flag Warning has been issued through 9pm.
Main impacts in this area include lightning occurring in an area
that has been dry, especially away from any heavy rain cores, and
gusty outflow winds that could increase fire spread. Tomorrow,
soundings show thunderstorms with similar characteristics and
threats as today, but highest chances will be further confined to
the mountains. Areas above that had a 10 to 20 percent chance of
thunderstorms will see chances much closer to 10 percent.

Monday through Friday: The low off the PNW coast will remain there
through the middle of the week, resulting in higher heights building
over the region to start the work week. With waves still moving
through, chances of precipitation and isolated thunderstorms remain
Monday and Tuesday, but are confined only to the mountains with
areas elsewhere having near zero chances. These chances will taper
off after Tuesday as a warmer and drier air mass moves in. Near the
end of the week, a quarter of the clusters show the low moving
northeastwards and towards the region, which would favor a cooler,
wetter end of the week. However, 75 percent of the clusters favor
continued ridging over the area as the offshore low weakens.
Temperatures will remain at or just above normal through mid-week,
then warm to 4-6 degrees warmer than normal as ridging remains over
the area. /AS

&&

.AVIATION...
18Z TAFs: VFR conditions will prevail through the 24 hour TAF
period with isolated MVFR visibilities possible due to smoke.
Confidence in visibility impacts is too low at this time to
bring TAF visibilities lower than 6SM for all terminals apart
from EAT. Smoke models keep EAT at MVFR/IFR for the majority of
the TAF period. The threat of showers and, to a lesser degree,
thunderstorms, will be present across much of the region through
around 06Z. GEG, SFF, COE, PUW, and LWS all have a TEMPO group
for showers. The chance for thunderstorms is too low to include
in TAFs at this point, though LWS has recorded a couple
instances of thunder in their METARs so far this evening. After
around 06Z, winds become light. There is a chance for
thunderstorms and showers tomorrow as well, but chances are low
enough to not include in TAFs at this time.

FORECAST CONFIDENCE AND/OR ALTERNATE SCENARIOS: High confidence
in smoke and haze continuing to impact local terminals, but low
confidence in extent of reduced vis/cigs. High confidence on
showers and isolated thunderstorms being present in parts of
the region Saturday afternoon but low confidence on storms
impacting specific TAF sites. This is the most impactful high
alternate scenario and any incoming thunderstorms would result
in amendments. /AS

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

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        56  88  57  89  59  87 /  30  20  20   0   0  10
Coeur d`Alene  56  87  57  88  59  86 /  30  20  20   0  10  10
Pullman        49  86  51  87  51  84 /  30  20  20   0  10   0
Lewiston       61  91  64  92  63  91 /  30  20  20   0  20  20
Colville       46  86  47  87  48  86 /  20  20  20   0  20  10
Sandpoint      49  82  50  84  51  82 /  20  20  20   0   0  10
Kellogg        54  83  55  84  56  82 /  30  20  20   0   0  10
Moses Lake     58  89  59  91  58  89 /  10   0   0   0   0   0
Wenatchee      65  88  66  90  66  89 /  20   0  10   0   0   0
Omak           61  89  61  91  62  90 /  40  10  10   0   0   0

&&

.OTX WATCHES/WARNINGS/ADVISORIES...
WA...Air Quality Alert until noon PDT Tuesday for Central Chelan
     County-Okanogan Highlands-Okanogan Valley-Upper Columbia
     Basin-Waterville Plateau-Wenatchee Area-Western Chelan
     County-Western Okanogan County.
     Red Flag Warning until 9 PM PDT this evening for Lower Palouse
      -Snake River (Zone 709).
ID...Air Quality Alert until noon PDT Tuesday for Lewis and
     Southern Nez Perce Counties-Lewiston Area.

&&

$$