209
FXUS66 KOTX 040527
AFDOTX

Area Forecast Discussion
National Weather Service Spokane WA
1027 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 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...
06Z TAFS: West winds have decreased into the 10 to 20 mph range
across the majority of the Inland Northwest after a windy day. Our
next round of light rain will spread east of the Cascades around
12z with the most significant stratiform precipitation occurring
south of Interstate 90. Ceilings of 2000 ft or less are progged by
the HREF and GFS MOS at Pullman, Spokane, and Coeur d`Alene with
the arrival of the light rain. More post-frontal wind will develop
after 21z and persist into the evening with gusts of 25 to 35kts
at Wenatchee, Moses Lake, Spokane, Couer d`Alene and Pullman.

FORECAST CONFIDENCE AND/OR ALTERNATE SCENARIOS:
Confidence in ceilings in the 12z-20z time frame are moderate.
Guidance is in good agreement with ceilings between 1000-2000 feet
at GEG, SFF, COE, PUW and smaller airports like Deer Park,
Sandpoint, and Kellogg. However, amendments may be needed to
refine the start and end time of the low clouds. /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        44  66  41  68  45  78 /  10  50   0   0   0   0
Coeur d`Alene  43  62  43  66  45  77 /  10  70  10   0   0   0
Pullman        41  61  43  66  44  77 /  20  70  10   0   0   0
Lewiston       51  69  53  76  52  86 /  30  60  10   0   0   0
Colville       35  64  35  69  39  78 /  10  50  10   0   0   0
Sandpoint      41  59  41  65  43  75 /  20  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 /  20  30   0   0   0   0
Wenatchee      49  69  47  75  51  84 /  20  40   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 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 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.

&&

$$