952
FXUS66 KOTX 200451
AFDOTX

Area Forecast Discussion National Weather Service Spokane WA 412 PM
PDT Fri Jul 19 2024

.SYNOPSIS...
Strong high pressure will continue to amplify, bringing increasing
heat that will peak on Sunday, with widespread temperatures in the
100s and some areas reaching 110 or higher. A weather system will
bring lower temperatures beginning next Tuesday, but will also bring
increased winds, which, combined with dry weather, will bring
increased fire risk.

.DISCUSSION Today through Sunday Night: Excessive heat continues to
be of major concern, as temperatures will continue to increase past
already dangerous levels. Models are in good agreement that a strong
upper-level ridge will build into the area on Saturday and remain
potent on Sunday, with the ridge axis stalled over the area during
the weekend before slowly beginning to shift east into Monday.
Initial warming will be due to subsidence from the ridge, but upper-
level flow will become southerly on the back side of the ridge as it
shifts east, with 850mb temperatures forecast to reach as high as
32C on Sunday. The HRRR does show smoke from Oregon drifting
northward, which could abate temperatures slightly, but with little-
to-no forecast cloud cover through the weekend, surface heating will
be extreme. Heat Advisories are currently in effect through 11 am
PDT Saturday, with Excessive Heat Warnings in effect from 11 am PDT
Saturday through 8 PM PDT Monday. Vulnerable populations should plan
well in advance to find cooling, and animals should be brought
indoors if possible or given water, shade, and fans otherwise.

Monday through Thursday: On Monday, the 300mb low will continue to
strengthen in the Gulf of Alaska and reach farther south, bringing
west-to-southwest flow that will bring an embedded shortwave into
the region and allow the ridge to begin to break down, bringing a
bit lower surface temperatures but increasing wind, especially
central WA. Increasing winds in combination with extremely dry air
will be of concern for any existing fires. Forecast CAPE (100-200
J/kg), positive vorticity advection (lift), 200-850mb shear, and
elevated moisture raises concern for high- based thunderstorms
capable of dry lightning Monday.

Models indicate dry and breezy conditions will continue through next
week despite cooler temperatures Tuesday onward with high
temperatures in the upper 80s to mid 90s. Increased surface winds in
combination with continued extremely dry air will create multiple
days of elevated to critical fire weather conditions, which will be
closely monitored in the coming days. /Cooke

&&

.AVIATION...
06Z TAFS: A building upper level ridge will allow VFR conditions to
continue through the period. The only exception will be some hazy
conditions from smoke near wildfires that may reduce visibilities
along Lake Chelan and in the Methow Valley.

FORECAST CONFIDENCE AND/OR ALTERNATE SCENARIOS: With the exception
of smoke near wildfires confidence is high for continued VFR
conditions.

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

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        64 101  67 106  70 102 /   0   0   0   0   0   0
Coeur d`Alene  62  99  66 103  69 102 /   0   0   0   0   0   0
Pullman        59  97  63 102  63  98 /   0   0   0   0   0   0
Lewiston       71 107  72 112  75 107 /   0   0   0   0   0   0
Colville       53  99  56 104  60 101 /   0   0   0   0   0   0
Sandpoint      57  96  62 101  64 100 /   0   0   0   0   0   0
Kellogg        68  97  71  99  73 101 /   0   0   0   0   0   0
Moses Lake     61 102  65 109  68 102 /   0   0   0   0  10  10
Wenatchee      69 102  74 107  75 103 /   0   0   0   0   0   0 Omak
          64 104  68 110  74 108 /   0   0   0   0   0   0

&&

.OTX WATCHES/WARNINGS/ADVISORIES...
ID...Heat Advisory until 11 AM PDT Saturday for Central Panhandle
  Mountains-Coeur d`Alene Area-Idaho Palouse-Lewis and Southern Nez
Perce Counties-Lewiston Area-Northern Panhandle.

     Excessive Heat Warning from 11 AM Saturday to 8 PM PDT Monday
   for Central Panhandle Mountains-Coeur d`Alene Area-Idaho Palouse-
Lewis and Southern Nez Perce Counties-Lewiston Area- Northern
Panhandle.

WA...Heat Advisory until 11 AM PDT Saturday for Central Chelan
County-     Lower Garfield and Asotin Counties-Moses Lake Area-
Northeast Blue Mountains-Northeast Mountains-Okanogan      Highlands-
Okanogan Valley-Spokane Area-Upper Columbia Basin-     Washington
Palouse-Waterville Plateau-Wenatchee Area-     Western Okanogan
County.

     Excessive Heat Warning from 11 AM Saturday to 8 PM PDT Monday
     for Central Chelan County-Lower Garfield and Asotin
     Counties-Moses Lake Area-Northeast Blue Mountains-Northeast
     Mountains-Okanogan Highlands-Okanogan Valley-Spokane Area-
     Upper Columbia Basin-Washington Palouse-Waterville Plateau-
     Wenatchee Area-Western Okanogan County.

     Fire Weather Watch from Sunday afternoon through Sunday evening
     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)-Foothills of Central Washington Cascades (Zone
     705)-Methow Valley (Zone 704).

     Heat Advisory from 11 AM Saturday to 8 PM PDT Monday for Western
     Chelan County.

&&

$$