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019
FXUS66 KOTX 220457
AFDOTX

Area Forecast Discussion
National Weather Service Spokane WA
957 PM PDT Fri Jun 21 2024

.SYNOPSIS...
Warm and dry conditions will occur into Saturday with temperatures
warming into the 80s and 90s. A dry cold front on Sunday will
create elevated to critical fire weather concerns over portions of
central and eastern Washington with widespread breezy to windy
conditions. This will likely be followed by temperatures cooling
back down towards normal values by Monday. Another warm up arrives
on Tuesday and Wednesday before the next weather system enters on
Thursday.

&&

.DISCUSSION...

Today - Warm and dry conditions continue through this weekend. Am
watching cumulus buildups producing probably virga over rural
Boundary county right at the Canadian border. Deeper convective
towers are east of the shortwave trough axis in Western Montana. The
Pioneer Fire continues to show a hot spot on shortwave infrared
satellite imagery this afternoon producing additional smoke.

Sat - The shortwave trough off the coast of Alaska continues to
deepen the downstream northwest US ridge tonight yielding some of
the warmest temperatures of the year so far tomorrow. Temperatures
will be in the 80s and 90s regionwide. This poses a moderate
heatrisk. This means most individuals are sensitive to heat,
especially those without effective cooling and/or adequate
hydration.

Sun - As the trough moves closer to the British Columbia coast
tomorrow night, the 500 mb height gradient starts to tighten. A dry
cold front will sweep across the region leading to elevated to
critical fire weather conditions for parts of the region. Sustained
winds of 10 to 25 MPH with gusts up to 40 MPH in combination with
relative humidity of 12-25% will be found from the Columbia Basin
into the Palouse, West Plains, and even nosing up into southern
Stevens, Pend Oreille, and Ferry counties. Uncertainty is present
with the deep marine layer on the west side of the Cascades banking
up into the crest. Will RH`s remain above critical thresholds for
those valleys along the East Slopes of the Cascades? Not sure yet.
/Butler

Monday through Friday: A cooler day Monday in the wake of the
cold front passage Sunday. Temperatures will be near average for
late June, which is upper 70s to mid 80s. Mostly clear skies and
winds lighter than Sunday is expected. A transient ridge moves
through Tuesday, and Wednesday we will see southwesterly flow
ahead of the next weather system. This will bump up our
temperatures above average- in the mid 80s to lower 90s. Wednesday
there is some instability in the afternoon to see some showers
along the Cascade crest and the Canadian border, with less than a
20% chance of thunderstorms right along the Canadian border.
Thursday a low pressure system will move through the region.
Thursday poses a better chance to see showers across the region.
Parts of the Columbia Basin and east slope valleys will likely
miss out, but other locations have a 20-50% chance of showers.
There is also a 15-30% chance of thunderstorms across northern WA
and ID. Winds will increase as well, and currently we have gusts
20 to 25 mph...but that could change as we get closer to the
event. Friday a ridge starts to build off the west coast and
showers with isolated thunderstorms continue for parts of the
Inland Northwest. Temperatures will cool Thursday to near average
and Friday to below average readings.

Next Weekend: For those looking towards next weekend....the
clusters have varying scenarios, with a near 50/50 split for
Saturday with the trough remaining over the area or a ridge
building in. Then Sunday the clusters start leaning toward a
higher probability of a ridge scenario. So...at this time
Saturday there could be some mountain showers up north closer to
the Canadian border and Sunday looks dry. Temperatures Saturday
will be in the 70s to lower 80s, with temps warming about 5
degrees for Sunday. /Nisbet

&&

.AVIATION...
-- Changed Discussion --
06z TAFS: The air mass under a shortwave ridge of high pressure
will be dry and warm this weekend. For tonight through Saturday
evening, surface winds will be light and clouds will generally be
above 10 thousand feet.

FORECAST CONFIDENCE AND/OR ALTERNATE SCENARIOS:
High confidence in VFR conditions through 00z Sunday. /GKoch
-----------------------

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
-- End Changed Discussion --

&&

.PRELIMINARY POINT TEMPS/POPS...
Spokane        56  89  59  83  48  77 /   0   0   0   0   0   0
Coeur d`Alene  54  85  56  80  48  74 /   0   0   0   0   0   0
Pullman        54  87  58  79  46  74 /   0   0   0   0   0   0
Lewiston       60  95  64  92  56  84 /   0   0   0   0   0   0
Colville       49  87  50  80  41  77 /   0   0   0   0   0   0
Sandpoint      49  82  54  78  45  73 /   0   0   0   0   0   0
Kellogg        58  84  60  77  50  71 /   0   0   0   0   0   0
Moses Lake     59  95  58  85  48  82 /   0   0   0   0   0   0
Wenatchee      66  92  60  80  53  81 /   0   0   0   0   0   0
Omak           59  92  56  85  49  81 /   0  10   0   0   0   0

&&

.OTX WATCHES/WARNINGS/ADVISORIES...
ID...None.
WA...Fire Weather Watch from Sunday afternoon through Sunday evening
     for Colville Reservation (Zone 702)-Eastern Columbia Basin
      -Palouse  -Spokane Area (Zone 708)-Foothills of Central
     Washington Cascades (Zone 705)-Lower Palouse  -Snake River
     (Zone 709)-Waterville Plateau (Zone 706)-Western Columbia
     Basin (Zone 707).

&&

$$