938
FXUS66 KOTX 032143
AFDOTX

Area Forecast Discussion
National Weather Service Spokane WA
243 PM PDT Mon Jun 3 2024

.SYNOPSIS...
Strong winds gusts will continue through into this evening, before
decreasing around sunset. A weaker weather system on Tuesday will
keep winds breezy and bring additional precipitation far eastern
Washington and north Idaho. A significant warming trend will then
commence mid week into the weekend. Very warm temperatures in the
mid 80s to mid 90s is expected Friday into the weekend.

&&

.DISCUSSION...
Monday night through Tuesday: Building high pressure behind todays
cold front passage has created a strong west-southwest pressure
gradient across the Inland Northwest this afternoon. Current values
of +14.4 mb from Portland to Glacier Park and even +12.7 mb from
Yakima to southern Alberta are supporting sustained winds of 25 to
35 mph. Strong winds aloft in the post frontal air mass are mixing
down to the surface with gusts up 40 to 50 mph across much of the
area. Radar continues to show showers across eastern Washington and
north Idaho, but have decreased in coverage and intensity compared
to earlier in the afternoon. These stronger winds will begin to
subside in the evening as the boundary layer decouples from the
stronger winds aloft.

Another plume of moisture will move into the region Tuesday morning
as a low pressure system moves onshore central British Columbia and
the associated front front moves across Washington. The strongest
upper level dynamics will remain north into British Columbia, but
modest warm air advection combined with upslope flow across eastern
Washington and the Idaho Panhandle ahead of the front will support
precipitation in these areas. The precipitation amounts have
increased quite a bit compared to 12 hours ago with an additional
0.15 to 0.25 inches forecasted across the Palouse through Tuesday
morning. Warming temperatures aloft with an upper level ridge
building from the south will limit post-cold front shower
development with the best chances for showers and isolated lightning
across the northeast mountains and north Idaho Tuesday afternoon.

Winds will increase again Tuesday afternoon with the cold front
passage. However, the surface low will move across northern British
Columbia, with a weaker pressure gradient across the Inland
Northwest compared to Monday. Because of this, we arent expecting
winds to be as strong as today, but winds gusts 35 to 45 mph will be
possible across the lee of the Cascades through the Basin and across
the Palouse and up into the Spokane area. The best chances to see
wind gusts above 45 mph will be across the Waterville Plateau and
the northern Columbia Basin where there is a 70-80% chance. /vmt

Wednesday through Sunday: An intensifying ridge of high pressure
will usher in a significant warming and drying trend, with
temperatures peaking on Saturday. By Friday, but especially on
Saturday, the rising temperatures will elevate the NWS Heat Risk to
moderate level. This increase in heat risk will affect most
individuals sensitive to high temperatures, particularly those
lacking effective cooling and adequate hydration.

On Sunday, the high pressure ridge will shift eastward, leading to a
change in the weather pattern. An upper-level southwest flow will
bring enough moisture to generate cloud cover spreading from west to
east. There will be a slight chance of showers and thunderstorms,
which will bring slightly cooler temperatures. Additionally, wind
spreads will increase, with possibly gusts, including outflows from
any developing showers and thunderstorms. This shift signifies a
transition from the intense heat of the preceding days to a more
varied and potentially stormy weather pattern, providing some relied
from the peak temperatures earlier in the week. /KM

&&

.AVIATION...
18Z TAFS: Cold front has pushed through the region with convection
firing up across eastern Washington and north Idaho. Much drier
air behind the cold front will allow ceilings to return to
primarily VFR across the region outside of areas of convection
where quick reductions to MVFR are possible. Low topped
thunderstorms up to around 23-25 kft will bring the risk for
strong outflow winds, small hail, and heavy rain primarily to
KGEG- KSFF- KCOE- KCQV- KDEW- KSZT through 22Z with thunderstorms
moving quickly to the east at 30-40 kts. Convection will be
capable of producing wind gusts up to 45-50 kts at these airports.
Post frontal winds of 20-30 kts with gusts up 35-45 kts will
continue through the afternoon into the early evening before the
pressure gradient relaxes overnight with the arrival of a weaker
frontal system. Ceilings with this system will lower to MVFR/IFR
around KPUW-KLWS northward to KGEG-KCOE early Wednesday morning.

FORECAST CONFIDENCE AND/OR ALTERNATE SCENARIOS:
Confidence is low that thunderstorms will impact airports today
with a 25% chance at KGEG-KSFF-KCOE-KCQV-KDEW-KSZT airports. There
is moderate confidence for a return to MVFR ceilings for KGEG-
KSFF-KCOE-KPUW-KLWS between 12-14Z with the next round of light
rain.

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

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        44  66  41  68  45  78 /  10  40   0   0   0   0
Coeur d`Alene  43  62  43  66  45  77 /  10  60  10   0   0   0
Pullman        41  61  43  66  44  77 /  10  60  10   0   0   0
Lewiston       51  69  53  76  52  86 /  20  50  10   0   0   0
Colville       35  64  35  69  39  78 /  10  50  10   0   0   0
Sandpoint      41  59  41  65  43  75 /  30  80  40   0   0   0
Kellogg        44  57  45  66  47  77 /  20  80  40   0   0   0
Moses Lake     48  74  42  75  47  84 /  10  20   0   0   0   0
Wenatchee      49  69  47  75  51  84 /  20  30   0   0   0   0
Omak           44  73  41  74  46  81 /  10  20   0   0   0   0

&&

.OTX WATCHES/WARNINGS/ADVISORIES...
ID...Wind Advisory until 7 PM PDT this evening for Northern Panhandle.

     Wind Advisory until 11 PM PDT this evening for Central Panhandle
     Mountains-Coeur d`Alene Area-Idaho Palouse-Lewis and
     Southern Nez Perce Counties-Lewiston Area.

WA...Wind Advisory until 7 PM PDT this evening for Northeast
     Mountains.

     Wind Advisory until 11 PM PDT this evening for Lower Garfield
     and Asotin Counties-Moses Lake Area-Northeast Blue
     Mountains-Spokane Area-Upper Columbia Basin-Washington
     Palouse-Waterville Plateau-Wenatchee Area.

&&

$$