253
FXUS66 KOTX 160945
AFDOTX

Area Forecast Discussion
National Weather Service Spokane WA
245 AM PDT Tue Jul 16 2024

.SYNOPSIS...

Hot and dry weather will continue this week with widespread upper
90s and triple digit temperatures. On Wednesday there is chance of
thunderstorms across the region containing little to no rainfall.

&&

.DISCUSSION...

Today through Wednesday night: Upper level ridge will have its axis
placed over Northwest Montana through most of this time interval.
This will allow for a warm/hot southwest flow on the west side of
the ridge axis to continue to allow for a warming trend through
Wednesday and beyond. In addition it appears a negatively tilted
upper level shortwave will run up the west side of this ridge and
have enough upper level moisture and instability to allow for a
mention of low precipitation producing (dry) thunderstorms Wednesday
and Wednesday night. Lightning will raise concerns for new fire
starts across the landscape. In addition, gusty outflow winds could
result in fire spread with any new starts. A Fire Weather Watch has
been issued for several areas of North Central Washington Wednesday.
Pioneer Fire near lake Chelan will continue to produce smoke and
impact air quality around Lake Chelan, and portions of the Methow
Valley. The Department of Ecology has an Air Quality Alert until for
Chelan and Okanogan counties in effect until further notice.
/Pelatti

Thursday to Monday: A ridge rebounds over the region this period,
building over the northern Rockies and helping to promote a
warming trend. Models are in good agreement in temperatures
pushing well above normal, with many areas pushing into the 100s
by the weekend, i.e. more dangerous heat potential. There are a
couple shortwaves that ride up the west side of the ridge around
Friday and again around Sunday. However they appear to just skim
the western CWA or remain just west and do not encounter the
instability that we see Wednesday. So the forecast remains dry. A
broader trough starts to approach toward early next week, leading
to some increased wind later Monday (into next Tuesday) especially
closer to the Cascades. Looking a little beyond the next seven
days, as we head into next week we will keep an eye on that
offshore trough which may shift inland to dampen the ridge over
the region and cool things off perhaps closer to seasonal norms.
Models still don`t show much of a risk for precipitation with any
dampening of the ridge, but it would come with increase winds.
Just how strong those may be has low confidence but this will be
monitored especially for fire weather concerns. /Solveig

&&

.AVIATION...
06Z TAFS: Skies will be mainly cloud-free through the night and
into Tuesday. High clouds over Oregon aren`t expected to make much
northward progress as moisture above 20 thousand feet encounters
strong upper level high pressure. Drainage winds along the East
Slopes of the Cascades will push smoke from the Pioneer Fire down
Lake Chelan into the Chelan and Methow Valley airports. Some minor
visibility reductions will also be possible at Ephrata and Moses
Lake Tuesday morning before light south winds develop around noon.

FORECAST CONFIDENCE AND/OR ALTERNATE
SCENARIOS: With the exception of smoke near the Pioneer Fire,
there is high confidence in VFR conditions. /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

&&

.PRELIMINARY POINT TEMPS/POPS...
Spokane        98  64  99  64  99  65 /   0   0  20  20   0   0
Coeur d`Alene  95  61  97  63  96  63 /   0   0  10  20   0   0
Pullman        93  60  95  60  94  60 /   0   0  20  10   0   0
Lewiston      103  69 104  71 105  70 /   0   0  20  10   0   0
Colville       95  55  97  54  97  55 /   0   0  20  20   0   0
Sandpoint      93  58  96  56  94  58 /   0   0  10  20   0   0
Kellogg        91  67  95  68  94  67 /   0   0  10  20   0   0
Moses Lake    100  63 102  63 102  63 /   0   0  20  10   0   0
Wenatchee     100  75 100  71 102  69 /   0   0  20  20   0   0
Omak          103  67 103  66 104  66 /   0   0  20  20   0   0

&&

.OTX WATCHES/WARNINGS/ADVISORIES...
ID...Heat Advisory from noon today to 10 PM PDT Thursday for Coeur
     d`Alene Area-Idaho Palouse-Lewiston Area.

WA...Heat Advisory from noon today to 10 PM PDT Thursday for Central
     Chelan County-Lower Garfield and Asotin Counties-Moses Lake
     Area-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 Colville Reservation (Zone 702)-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)-
     Foothills of Central Washington Cascades (Zone 705)-Methow
     Valley (Zone 704)-Okanogan Highlands and Kettle Mountains
     (Zone 699)-Okanogan Valley (Zone 703)-Waterville Plateau
     (Zone 706).

&&

$$