456
FXUS66 KOTX 231737
AFDOTX

Area Forecast Discussion
National Weather Service Spokane WA
1037 AM PDT Thu May 23 2024

.SYNOPSIS...
Today will feature scattered afternoon showers and thunderstorms
mainly across north Idaho as well as north central and northeast
Washington. Friday, Saturday and Sunday will cool with highs in
the 60s and low 70s with chances for afternoon and evening showers
and thunderstorms. Memorial Day will be the warmest and driest
day of the holiday weekend with afternoon temperatures well into
the 70s. A return of cool, wet weather expected midweek.

&&

.DISCUSSION...
Today and Tonight: For most of the region, a brief break between
systems is expected. The Wednesday Low will continue to move
South and East, while another Low begins to develop over Gulf of
Alaska. It will lead to a dry, cool day for the Cascades and areas
South of Hwy 2 and I-90. A Low over Central Washington will push
a shortwave trough over North Washington and North Idaho. It will
bring precip chances to these areas. Models are indicating Cape
values of up to 200 J/Kg through the afternoon and bringing a
chance of thunderstorms in these areas. Most areas are expected to
receive a couple of hundredths to a tenth of an inch. Portions of
Northeast Washington and North Idaho could receive near 0.25".
Shower activity will taper off overnight as a brief weak ridge
builds over the region. Highs for the day will be will in the 60s
to low 70s. Overnight lows will be in the 40s.

Friday: The ridge will start to weaken early in the morning as
the next Low begins to push into the Pacific Northwest coast.
Precip chances will gradually increase through the day. It will
mainly bring afternoon showers over the mountain portions of the
Inland Northwest, while the Basin will remain relatively dry.
Highs will continue to be in the 60s and low 70s. Overnight lows
will be in the 40s. /JDC

Saturday through Wednesday: The weekend will start off with a robust
shortwave moving through bringing breezy winds, intermittent showers
across the region, and thunderstorms in the northern mountains.
Areas that will see the most rainfall with this wave include the
northern mountains, Cascade Crest, eastern third of WA, Blue
Mountains, and ID Panhandle. Probabilities for greater than 0.1
inches of rain range from 40 to 70 percent in those areas. Wind
gusts of 20 to 30 mph are expected for most locations across the
region.

By Sunday the shortwave will have moved to our east, placing us in
zonal westerly flow. Sunday is looking mainly dry with the exception
of a few afternoon showers possible for orographically favored areas
- i.e., the Cascade Crest and ID Panhandle mountains. High
temperatures Saturday and Sunday will be typical for this time of
year in the 60s and 70s, and lows will be in the 40s - also right
around what is seasonally normal.

With the new week will come a new pattern in the form of a ridge of
high pressure. An upper-level ridge will move in on Monday,
squashing any remaining shower chances and sending temperatures well
into the 70s and even low 80s for some spots. How long the ridge
will stick around is uncertain though, with some models suggesting
it will move out by Tuesday and others keeping it over us until
Wednesday. If the ridge remains over us through the day on Tuesday,
temperatures on Tuesday will be even warmer than those on Monday,
and highs in the 90s won`t be out of the question for the deep
Columbia Basin southeast of Moses Lake. Current ensembles are giving
this area a 10 to 20 percent chance of hitting the 90s on Tuesday.

After the ridge moves out, another shortwave trough will be quick to
take its place, which means cooler temperatures and more showers and
thunderstorms are likely in store for us over the latter half of
next week. More details on that as it gets closer. /Fewkes


&&

.AVIATION...
18Z TAFS: MVFR conditions over extreme Eastern Washington and
North Idaho will gradually improve to VFR through the rest of the
morning. The atmosphere will destabilize this afternoon with a
30% chance of showers and thunderstorms mainly over the northern
mountains and KGEG-KSFF-KCOE.

FORECAST CONFIDENCE AND/OR ALTERNATE SCENARIOS:
Low confidence on showers over the TAF sites in extreme eastern
Washington and North Idaho this afternoon. /Butler

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

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        63  44  69  47  63  42 /  10  20  20  20  30  10
Coeur d`Alene  59  44  67  46  60  44 /  20  30  20  30  40  10
Pullman        59  39  66  44  58  40 /   0  10  20  40  30  10
Lewiston       66  45  73  51  66  47 /   0  10  20  40  30  10
Colville       64  38  68  41  63  36 /  70  60  50  40  60  20
Sandpoint      58  44  64  44  60  42 /  60  50  40  40  60  20
Kellogg        57  45  64  47  56  44 /  20  20  40  40  60  20
Moses Lake     73  43  73  47  70  42 /  10  10  10  10  10   0
Wenatchee      71  46  70  49  66  46 /   0   0  10  10  10   0
Omak           72  44  72  47  67  44 /  30  10  20  20  20   0

&&

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

$$