464
FXUS66 KOTX 191817
AFDOTX

Area Forecast Discussion
National Weather Service Spokane WA
1117 AM PDT Thu Mar 19 2026

.KEY MESSAGES...

- Warming Trend: Temperatures above seasonal averages through
  Friday with widespread afternoon highs in the 60s to low 70s.

- Hydrology Concerns: Rain on snow in the Cascades and Idaho
  Panhandle will lead to rises on creeks and streams.

- Breezy Winds: Persistent southwest winds are forecast with
  afternoon gusts up to 30-35 mph through Friday.

&&

.SYNOPSIS...
A warmer and periodically breezy pattern continues through
Friday. Snowmelt combined with moderate to heavy precipitation
in the North Cascades and light precipitation over the Idaho
Panhandle mountains will lead to rises on rivers. A cold front
Friday night will bring cooler temperatures for the weekend with
dry conditions expected Saturday through Monday. Unsettled
conditions will return Tuesday with a return of snow in the
mountains.

&&

.DISCUSSION...
Today through Friday: The west portion of the U.S. will be dominated
by anomalously strong upper level ridge centered over southern
California, southern Nevada, and Arizona. Those under this ridge are
experiencing record breaking heat; whereas, in our corner of the
U.S. a moderately strong Atmospheric River is being directed into
western Washington and across the Inland Northwest. There are
differences with the weather conditions across the state of
Washington though. The bulk of the moisture with this AR is
falling across the western portion of the state with a
substantial rain shadow in the lee of the Cascades. It`s a stark
contrast across the mountain change. The windward side of the
slopes have experienced 4, 5, 6 inches of rainfall over the
past few days with this AR in place and it`s causing flooding
impacts on that side of the state. The magnitude of the moisture
streaming across isn`t the highest of the multiple ARs we`ve
seen over the winter into early March, but the duration of this
current AR is definitely notable.

Our weather will experience very little change over the next 36
hours. Moderate rainfall will continue to pile up across the Cascade
crest as moisture slops over. Ripples within the jet will also carry
a fraction of this moisture through with light rain occurring east
of the Cascades primarily over northeast Washington into the Idaho
Panhandle. The Northern Panhandle will see more consistent light
rain through Friday with between a quarter of inch to up to around
an inch of additional rainfall. The Selkirks and Cabinets will see
these higher rainfall totals of up an inch plus. The only area of
concern for hydrology related impacts will be in the east slopes of
the Cascades. There won`t be as significant of flooding impacts as
what the west side will be experiencing, but rivers and small
streams and creeks will also be experiencing rises. Part of the
reason will be due to the rain at the crest, but more significantly
so will be from snowmelt. Temperatures are warming up into the 60s
across the valleys with lows only cooling into the mid to upper 40s.
Snow has ripened across the mid slopes and we are seeing a steady
flux of water percolating through the watersheds. The Stehekin
River in particular will see a significant rise and impact the
community of Stehekin over the next couple of days. Additional
flooding is not expected at this time, but we will have to
continue to monitor the hydrographs in this area for additional
flood advisories and/or warnings. The flood warning for Stehekin
remains valid through 11PM Sunday. It will take at least a
couple of days for this river to drop after it crests sometime
on Saturday.

A cold front will finally swing through on Friday night into early
Saturday. Colder air with the front will drop temperatures back to
around normal for the weekend. Frontogenesis will also produce
a band of precipitation along the front. This band will largely
develop across southeast Washington into the southern to
central Idaho Panhandle Friday night. There will be a period of
more moderate precipitation rates, but not expected to be
impactful. Snow levels also drop with the front and light snow
can be expected over the Cascade crest. This will include over
Stevens Pass, but doesn`t look to be enough to cause travel
impacts. Winds will also continue to remain breezy in the warm
sector through Friday and then also with the cold front passage.
Winds along are not particularly strong though with most
exposed areas, including the Columbia Basin, expected to see
wind gusts up to around 25-35 mph at times.

Saturday night through Monday: This will be a dry period in a post
frontal air mass. Temperatures will be cooler and near normal for
mid March. The cooler temperatures slow melt way down and allow for
rivers and small streams to peak and come down.

Monday night through Thursday: There is a lot of uncertainty with
low pressure trough passing through Tuesday into Wednesday. Most of
the ensemble members indicate a weaker to more modest cold front
passage, but there`s a 10-20% chance or so for a stronger cold
front. The 00Z operational GFS is one of these model solutions that
depicts a stronger shortwave. Confidence is high for temperatures to
be seasonal. Snow levels will be low enough for accumulating snow in
the mountains, and this may result in travel impacts for our
mountain passes Tuesday into Wednesday. These impacts look to be
minor. The operational GFS in particular shows strong winds mixing
down and a tight pressure gradient. This is one of those outlier
scenarios that would suggest the potential for 40-50 mph winds, but
unlikely that this scenario will play out. /SVH

&&

.AVIATION...
18Z TAFS: A moisture plume continues to be directed into the
Pacific Northwest with with precipitation primarily falling in
the mountains. This will bring periods of light rain to
terminals early this afternoon and overnight tonight. Radar does
show light returns moving across southeast Washington and the
central ID Panhandle, but a dry boundary layer will keep this
falling primarily as light sprinkles virga. Another round of
light rain is expected to move in from the south between 03-12Z,
but ceilings are expected to remain about 5 kft.

Westerly winds are expected increase shortly with gusts 17-28
knots mixing to the surface at KGEG-KSFF-KMWH-KPUW-KLWS through
the afternoon.

FORECAST CONFIDENCE AND/OR ALTERNATE SCENARIOS:
High confidence for conditions to remain VFR through the
period. Low to moderate confidence in light precipitation making
it to the surface 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        50  65  42  54  30  51 /  40  30  40  20   0   0
Coeur d`Alene  48  63  42  54  29  51 /  60  50  70  30   0   0
Pullman        49  68  44  51  30  51 /  20  10  50  50  10   0
Lewiston       50  73  49  59  34  56 /  10  10  40  50  10   0
Colville       49  63  39  56  28  53 /  60  60  30  20   0   0
Sandpoint      46  56  41  51  29  48 /  80  80  80  40  10   0
Kellogg        50  63  44  50  31  49 /  60  50  80  60  10   0
Moses Lake     52  71  42  57  30  56 /  20  20  10   0   0   0
Wenatchee      51  65  40  52  32  54 /  40  50  20   0   0   0
Omak           49  65  37  56  30  53 /  40  50  10   0   0   0

&&

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

&&

$$