972
FXUS66 KOTX 052155
AFDOTX

Area Forecast Discussion
National Weather Service Spokane WA
255 PM PDT Sat Sep 5 2026

.KEY MESSAGES...

- Cool and showery weather expected through Labor Day Weekend
  with isolated thunderstorms.

- A warming and drying trend returns around the middle of next
  week.

&&

.SYNOPSIS...
Active weather sticks around through Labor Day Weekend with
scattered showers, isolated thunderstorms, and cooler than normal
temperatures. A warming and drying trend commences around the middle
of next week as higher pressure returns to the region.

&&

.DISCUSSION...
This afternoon and tonight through Monday: The Inland NW will
see evolving rain chances this period, along with a risk
embedded thunderstorms, and a marginal risk (5-14% chance per
WPC) for excessive rainfall over Idaho and the far eastern
fringes of WA late Sunday into Monday morning. Tonight a broad
low, centered near the Oregon coast, is impacting much of the
Pacific Northwest. The south to southeast flow into our area
will work with daytime instability and an impulse riding north
to bring chances for showers and isolated thunderstorms through
sunset. The best chances will remain near the Cascades to north-
central WA, with pops near 20-59%. Secondary chances will be
found from near the Blue Mountains north toward the Spokane/CdA
area and northeast WA/N ID mountains, with pops around 10-20%.
After about 8-9 PM the risk will weaken, lingering near the
north to Cascades to north-central WA. Other chances start to
back into the ID/MT border overnight as the broad low starts to
move. Lows will largely be in the 40s, with some low 50s in the
L-C valley and near the Cascades. Some patchy fog is also
possible again heading into Sunday morning in the sheltered
northeast valleys and higher Palouse.

Then heading into Sunday and Monday the offshore low moves east
across Oregon and toward the lower ID Panhandle. This will work
with a shifting deformation axis and deepening PWATs over
southeast WA through the ID Panhandle to bring increasing
precipitation chances. Chances remain limited to the ID/MT
border in Sunday morning, then start expanding to eastern WA in
the afternoon and eventually south-central WA by Sunday evening.
PoPs rises to 60-90% over southeast/east-central WA and central
and southern ID Panhandle. Within this region is also increasing
convective instability with CAPE values between averaging
between 500-1000 J/kg. Forecast soundings are modestly saturated
this period and skinny CAPE, with supports locally heavier rain
potential rather than large hail or strong winds.

The WPC has marginal risk for excessive rainfall over the WA
counties along the ID border and across the ID Panhandle for
Sunday through early Monday. So we will have to watch for debris
flows near burn scars, rock slides, and rises on small creeks
and streams. The PWATs in that region sit between 0.75 to 1.0
inches. The higher probabilities are across the central and
southern ID Panhandle, where 24-hour probabilities from 5 PM
Sunday to 5 PM Monday for 0.50 inches are between 70-90%, 60-80%
for 0.75 inches and 30-60% for 1 inch. As we head into Monday
evening and overnight the low starts to shift east and the
precipitation potential starts to wane. By the overnight the
best chances linger over the north and central ID Panhandle,
bleeding a bit west into the northeast WA mountains, with PoPs
around 40-50% and slight chances into the Spokane areas.

As the low is starting to exit Monday winds will become breezy
through the day and early evening. West-southwest winds of 10-15
mph and gusts of 20-25 mph will be possible. Highs will be in
the 70s Sunday, then the 60s and 70s Monday with those cooler
readings over the east third of WA and ID under the higher rain
chances. Lows will be in the 40s to lower 50s.

Tuesday to Saturday: The Inland NW transitions to a drier
pattern with warming temperatures, before additional rain
chances arrive Friday into Saturday. A weak ridge to zonal
pattern develops Tuesday into Thursday, leading to the warming
temperatures that pushes highs into the 70s to low 80s
Wednesday, reaching the upper 70s to upper 80s by Thursday. A
trough the drops into toward the end of the week, bringing those
rain chances with highs dropping back to the upper 60s to upper
70s by next Saturday. /Solveig


&&

.AVIATION...
18Z TAFS: An upper-level low encompasses the Pacific Northwest
with embedded shortwaves bringing a mix of cloud types and
heights and wrap around showers across the region. For the TAF
sites, conditions will remain VFR through the period. Later this
morning, afternoon instability will bring showers and isolated
thunderstorms along the Cascades. These showers have a 30%
chance of impacting KEAT through 21z and including this in a
TEMPO group. For this evening there is a 10-20% chance of a band
of showers developing over eastern WA, including KPUW, KGEG,
KSFF but given low probability did not mention in TAF`s but will
be re-evaluated with 00z issuance.

FORECAST CONFIDENCE AND/OR ALTERNATE SCENARIOS: Low confidence
on thunderstorms this afternoon impacting any TAF sites. JW

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

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        48  75  50  68  49  74 /  20  20  60  50  20   0
Coeur d`Alene  47  74  49  65  47  72 /  20  20  70  70  50  10
Pullman        43  71  46  64  40  72 /  20  20  80  70  10   0
Lewiston       52  76  55  70  52  78 /  10  20  80  80  10   0
Colville       43  75  44  73  40  75 /  20  10  30  40  30   0
Sandpoint      47  71  48  63  42  70 /  20  20  60  70  60  20
Kellogg        45  72  48  59  47  69 /  10  40  80  90  60  10
Moses Lake     47  74  50  76  46  78 /   0  10  30  10   0   0
Wenatchee      52  75  57  77  56  80 /  10  10  10   0   0   0
Omak           50  76  50  77  50  79 /  20   0  10  20  20   0

&&

.OTX WATCHES/WARNINGS/ADVISORIES...
WA...None.
ID...None.

&&

$$