224
FXUS66 KOTX 272157
AFDOTX

Area Forecast Discussion
National Weather Service Spokane WA
257 PM PDT Wed Aug 27 2025

.KEY MESSAGES...

- Scattered showers with isolated thunderstorms through Thursday.
  Thunderstorms will be capable of heavy rainfall.

&&

.SYNOPSIS...
An area of low pressure will bring scattered showers and
isolated thunderstorms to the Inland Northwest through Thursday.
Thunderstorms will bring the potential for heavy rainfall
particularly in the Cascades and in the Idaho Panhandle.
Temperatures will cool into the 80s to low 90s through the rest
of the week.

&&

.DISCUSSION...
Tonight through Friday: A slow moving area of low pressure will
push across the Inland Northwest over the next couple of days. A
deformation band with steady light to moderate rain will push
northward through tonight into Thursday. This band is currently
pivoting across the southern Idaho Panhandle and southern
portions of eastern Washington at 2:30 PM Wednesday afternoon.
It will shift up across the Spokane/Coeur d`Alene area overnight
and across the northern zones by Thursday afternoon. A lot of
cloud cover with this band is limiting the destabilization of
lower levels of the atmosphere with convection being held at bay
for now. There is still potential for convective elements with
the deformation band that could bring more moderate rainfall
rates. Overall though, this rain will benefit the current
ongoing drought conditions across the area.

Clouds will clear across the southern portions of the area for
Thursday with a better potential for sunshine surface based
instability. Dew point temperatures will be in the 50s across
much of the region. A low pressure circulation will approach the
Cascades move across western Washington, and this looks to be a
favored area for the combination of moisture, instability, and
lift for thunderstorms to form. Convective temperatures look to
be hit early in the day with convection forming as early as
10-11 AM. P-wats will remain above one inch, which is abnormally
moist for our area. Thunderstorms will be moving slowly to the
west, but the threat of heavy rain with deeper convection on
Thursday is a concern for the Cascades. This is particularly so
for burn scars, but not exclusively so for just those
locations. A Flood Watch for Flash Flooding has been issued for
the Cascades in effect from 11 AM till 9 PM Thursday. The upper
level low pressure area will move very little from Thursday into
Friday. Friday afternoon will remain conditionally unstable
across the northern mountains where additionally diurnally
forced convection is expected to occur.

Friday night through Wednesday: Another upper level low pressure
system will move into the Northwest over the weekend. This one
will be slow moving as well shifting off of the eastern Pacific
into northwest Washington by Saturday afternoon. At the same
time, there will be energy rounding a ridge of high pressure in
the northern portion of the Gulf of Alaska diving south in
northwest flow across northern BC. This northern branch will act
to slow and even reverse the forward progression of the low
into Washington state. As such, bes chances for showers and
thunderstorms will be over the Cascades into the Okanogan
Highlands, but it won`t be accompanied by the same level of
moisture as what we are seeing currently.

The low retrograding early next week will result in high
pressure building back in over the Inland Northwest. This will
result in a warming and drying trend for Monday through
Wednesday. Widespread 90s will return, but temperatures won`t
get as hot as with the last heatwave we just came out of. /SVH

&&

.AVIATION...
18Z TAFS: An area of deformation developing north of an area of
low pressure will bring widespread light to moderate rain to the
Inland Northwest today. The focus for steady rain will be along
an east-west line from KLWS/KPUW to KMWH/KEPH/KEAT this
afternoon. The prognosis will be for this band to lift northward
into KGEG/KSFF/KCOE between 23-02Z late this afternoon.
Conditions will mostly be VFR with the rain until the lower
levels of the atmosphere moisten up. A caveat is persistent
smoke/haze out of Idaho into KPUW with MVFR conditions into the
early afternoon before rain scrubs out the hazy conditions.
There is potential for pockets of heavier rainfall and isolated
thunderstorms, but not enough confidence to include in the TAF
at this time. Wind gusts up to around 20 kts will be possible
with a dry sub cloud later before moistening up today.

FORECAST CONFIDENCE AND/OR ALTERNATE SCENARIOS: High confidence
in continued VFR conditions through the TAF period. The HREF
model indicates a 30 percent chance for ceilings lowering down
to around 3,000 ft agl with late this afternoon into tonight
after 03Z at KLWS/KPUW and after 10Z at KGEG/KSFF/KCOE. Low
confidence for thunderstorms impacting airport terminals today.
/SVH

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

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        64  81  59  88  59  92 /  40  30  10  10   0   0
Coeur d`Alene  64  77  59  85  59  91 /  40  40  10  10  10   0
Pullman        57  80  54  86  54  90 /  50  30  10   0   0   0
Lewiston       66  88  64  92  64  96 /  60  30   0   0   0   0
Colville       56  81  51  88  49  91 /  30  20  20  20  10   0
Sandpoint      58  75  54  83  54  89 /  30  40  20  30  10   0
Kellogg        63  75  61  82  61  88 /  60  60  20  20  10   0
Moses Lake     65  87  60  92  60  95 /  40  20  10   0   0  10
Wenatchee      69  87  67  92  68  93 /  50  30  10   0   0  10
Omak           68  87  63  92  64  94 /  40  40  20  10  10   0

&&

.OTX WATCHES/WARNINGS/ADVISORIES...
WA...Flood Watch from Thursday morning through Thursday evening for
     Central Chelan County-Okanogan Highlands-Okanogan Valley-
     Wenatchee Area-Western Chelan County-Western Okanogan
     County.
ID...Air Quality Alert until 11 AM PDT Thursday for Central
     Panhandle Mountains-Idaho Palouse-Lewis and Southern Nez
     Perce Counties-Lewiston Area.

&&

$$