018
FXUS66 KOTX 081730
AFDOTX

Area Forecast Discussion
National Weather Service Spokane WA
1030 AM PDT Mon Jul 8 2024

.SYNOPSIS...
Hot temperatures will continue through the upcoming week. The
hottest days will be Tuesday and Wednesday with widespread triple
digit heat. Breezy to gusty winds return Wednesday with
increasing fire weather concerns.

&&

.DISCUSSION...

...ONGOING HEATWAVE DELIVERING NEAR RECORD HEAT THROUGH WEDNESDAY...
...INCREASED FIRE WEATHER DANGER THROUGH WEDNESDAY...

Key messages for the week

- Hot to very hot temperatures are here and will be in place through Wednesday
- Tuesday and Wednesday will deliver the hottest afternoon temperatures and warmest overnight lows
- Red Flag Warnings and Fire Weather Watches in effect for some areas MON through WED
- Temperatures cool 10 degrees Thursday then warm again heading into the weekend
- No precipitation is in sight

Heat:

Strong upper level has become established over the region and
will remain anchored through Tuesday then flatten on Wednesday as
shortwaves swing into southern BC. On Sunday, temperatures
reached the triple digits at locations like Lewiston, Ephrata,
Omak, Winthrop, Stehekin, Moses Lake, and Priest Rapids Dam.
Priest Rapids Dam was the winner coming in at 105F with Omak a
close second at 103F. The air mass will continue to warm today and
Tuesday with another 1-3 degrees of warming each consecutive day.
By Wednesday, we start to see temperatures come down 1-2 degrees
in Central WA and remain steady or possibly 1 warmer for Idaho and
eastern reaches of WA. Tuesday and Wednesday will feature the
hottest readings of this heatwave with numerous communities
between 102-110F. Overnight lows have been pleasant in our
northern mountain valleys but have remained in the upper 60s to
70s for our lowest elevations and Basin. Low temperatures will
also be coming up 1-3 degrees each night. Excessive heat warnings
are meant to capture the areas that will carry the greatest risk
for overnight lows of 65-75 offering little to no relief at night.
It is advised to take the heat seriously and follow precautions
to avoid heat stress. This includes taking breaks often, staying
hydrated, and finding air conditioned areas when applicable. Be
sure to check in occasionally on your furry friends, elders, and
other sensitive to heat.

Fire Weather:

Red Flags are currently in effect for the Cascades and Pioneer
Fire. This pattern has a history of rapid fire growth for these
fire zones given the hot temperatures, long burn periods (poor
overnight RH recoveries), and unstable weather conditions. Any new
starts anywhere in the region will also be exposed to these hot,
dry, unstable conditions and could result in rapid fire growth
where terrain/slope plays a role. Please be cautious out there. A
fire weather watch has been issued for Wednesday afternoon and
evening for Central WA. As the ridge begins to flatten, winds will
be on the increase region-wide. Central WA carries the greatest
risk for sustained winds of 15-20 mph with gusts near 30 mph. The
L-C Valleys, Foothills of the Blue Mountains, Palouse, eastern
Basin including Ritzville, Davenport, and Spokane, and Colville
Reservation are other areas that will be in the elevated status
meaning winds steady winds will be present but speeds are less
likely to reach sustained speeds of 15 mph or stronger. This will
need to be monitored over the next 24 hours for potential changes
in the guidance. Winds on Wednesday will come with temperatures in
the 90s-100s and RH values in the teens.

Smoke:

The Pioneer Fire burning south of Stehekin on Lake Chelan will have
high probabilities to remain active given the projected weather
pattern. Smoke from the fire will settle into the lake basin
overnight with a drift downlake toward Manson and Chelan overnight
and uplake during the day. Deeper plumes of smoke during the day
will bring the potential for smoke into the Methow Valley as well.
Air quality is likely to be impacted at times. Please refer to
fire.airnow.gov for the latest readings and smoke outlooks.

Thursday through Sunday:

Temperatures will cool 10 degrees on Thursday with a flatter
ridge in place with readings still in the 90s; we`ll call it warm
zonal flow. The air mass also becomes quite dry behind the front
with PWATs lowering from 0.50 to 0.25 Wednesday night and Thursday
so despite the cooling, RH values will remain very low with
continued elevated fire weather conditions. Overnight lows will
feel much better however with readings in the 50s-60s. The
thermometer will be on the rise again for the weekend. There is
still moderate uncertainty with the placement of an offshore low
and the re- amplification of the interior ridge. It is conceivable
that temperatures rebound back into the upper 90s or even lower
100s. What does seem likely is winds will remain "breezy" each
afternoon from THU-SAT with steady speeds 8-14 mph and gusts near
20 mph which could be problematic for any new ignitions given the
new state of the fuels following the heatwave. /sb

&&

.AVIATION...

18Z TAFS: VFR conditions will prevail at TAF sites. Local
reductions in visibility possible near and downwind of Lake Chelan
due to smoke from the Pioneer Fire, especially in the
ovenright/early morning hours.

FORECAST CONFIDENCE AND/OR ALTERNATE SCENARIOS: High confidence in
VFR conditions, except near Lake Chelan from wildfire smoke.

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

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       100  67 103  68 104  65 /   0   0   0   0   0   0
Coeur d`Alene  97  66 100  67 102  61 /   0   0   0   0   0   0
Pullman        96  64 100  65 101  60 /   0   0   0   0   0   0
Lewiston      105  73 109  74 111  70 /   0   0   0   0   0   0
Colville       98  59 101  60 102  57 /   0   0   0   0   0   0
Sandpoint      93  61 100  59  99  58 /   0   0   0   0   0   0
Kellogg        93  67  98  71 102  63 /   0   0   0   0   0   0
Moses Lake    104  67 107  68 107  65 /   0   0   0   0   0   0
Wenatchee     104  74 108  75 104  69 /   0   0   0   0   0   0
Omak          105  73 108  74 107  66 /   0   0   0   0   0   0

&&

.OTX WATCHES/WARNINGS/ADVISORIES...
ID...Heat Advisory until 10 PM PDT Wednesday for Central Panhandle
     Mountains-Northern Panhandle.

     Excessive Heat Warning until 10 PM PDT Wednesday for Coeur
     d`Alene Area-Idaho Palouse-Lewis and Southern Nez Perce
     Counties-Lewiston Area.

WA...Heat Advisory until 10 PM PDT Wednesday for Northeast Mountains-
     Okanogan Highlands-Western Chelan County.

     Excessive Heat Warning until 10 PM PDT Wednesday for Central
     Chelan County-Lower Garfield and Asotin Counties-Moses Lake
     Area-Northeast Blue Mountains-Okanogan Valley-Spokane Area-
     Upper Columbia Basin-Washington Palouse-Waterville Plateau-
     Wenatchee Area-Western Okanogan County.

     Fire Weather Watch from Wednesday afternoon through Wednesday
     evening for East Portion of North Cascades National
     Park/Lake Chelan National Recreation Area (Zone 697)-East
     Washington Central Cascades (Zone 696)-Foothills of Central
     Washington Cascades (Zone 705)-Methow Valley (Zone 704)-
     Okanogan Valley (Zone 703)-Waterville Plateau (Zone 706)-
     Western Columbia Basin (Zone 707).

     Red Flag Warning from noon today to 11 PM PDT Tuesday for East
     Portion of North Cascades National Park/Lake Chelan
     National Recreation Area (Zone 697)-East Washington Central
     Cascades (Zone 696)-East Washington North Cascades (Zone
     698).

&&

$$