433
FXUS66 KSEW 071904
AFDSEW

Area Forecast Discussion
National Weather Service Seattle WA
1204 PM PDT Sun Jul 7 2024

.SYNOPSIS...Hot and dry conditions will persist under a strong
upper level ridge through the first half of the week. Some relief
is expected around midweek as the ridge moves eastward and weakens.
However, above normal temperatures and no precipitation will remain.

&&

.SHORT TERM /TODAY THROUGH TUESDAY/...Satellite imagery depicts
mostly clear skies across the entire PNW at this hour. That is of
no surprise given a strong 500mb ridge amplifying over the region
leading to large-scale subsidence and well-above average
temperatures. Today, this ridge will remain largely in place and
into the rest of the short term forecast. Its axis will stretch
far into BC and the PNW Sunday-Monday before positioning over
Alberta and the Intermountain West by Tuesday. This period will
feature the hottest temperatures (15 to 20 degrees above normal)
as highs top out well into the 80s and 90s throughout W WA. Triple
digit values are not out of the question with the most likely
areas being Olympia south along I-5 and Cascade valleys and
foothills. The immediate coastline will be the coolest location
with highs staying put in the 60s and 70s. Overnight lows will
also remain in the lower 60s for areas inland, making for slow
relief from the daytime highs.

Widespread HeatRisk reaching moderate levels is expected for much
of W WA. Areas of major HeatRisk are favored in the Seattle metro
as well as the Olympic and Cascade valleys. This level of heat
affects anyone without effective cooling and/or adequate
hydration. As a result, a heat advisory is in effect through
Tuesday evening for most of the area through Tuesday evening.
Drink plenty of fluids, stay in an air-conditioned room if
possible, stay out of the sun, and check up on relatives and
neighbors.

.LONG TERM /WEDNESDAY THROUGH SATURDAY/...We`ll begin to see some
reprieve as we go into the long term forecast. The stubborn ridge
will push further eastward and flatten. An intrusion of marine
cooled air will then pool into W WA Wednesday-Thursday as
temperatures drop but still above average. Nevertheless, the
threat for heat related impacts should lessen so we`ll take our
wins where we can get them. Highs are to be in the mid 70s to mid
80s with coastal areas staying in the 60s.

McMillian

&&

.AVIATION...VFR conditions will continue as high pressure
dominates over the region. N/NE winds 5 kt or less this morning,
increasing again this afternoon back to 8 to 12 kt and becoming
more N/NW.

KSEA...VFR conditions through the TAF period. North winds 4 to 8 kt,
increasing in the afternoon back to 8 to 12 kt.

15/Maz

&&

.MARINE...High pressure still remains offshore, with a thermal
trough lingering over the west coast. North/northwesterly winds will
continue over the coastal waters through the weekend for generally
benign marine conditions.

A surface front will push across the area waters on Wednesday for
increased onshore flow and stronger pushes down the Strait of Juan
de Fuca. Winds will likely be elevated through this period and are
favored to remain that way through the end of next week.

Coastal seas 4 to 6 feet throughout the weekend, and will gradually
increase to 6 to 8 feet by the end of next week.

15

&&

.SEW WATCHES/WARNINGS/ADVISORIES...
WA...Heat Advisory until 10 PM PDT Tuesday for Admiralty Inlet Area-
     Bellevue and Vicinity-Bremerton and Vicinity-East Puget
     Sound Lowlands-Eastern Strait of Juan de Fuca-Everett and
     Vicinity-Hood Canal Area-Lower Chehalis Valley Area-
     Olympics-San Juan County-Seattle and Vicinity-Southwest
     Interior-Tacoma Area-West Slopes North Cascades and Passes-
     West Slopes North Central Cascades and Passes-West Slopes
     South Central Cascades and Passes-Western Skagit County-
     Western Whatcom County.

     Heat Advisory until 10 PM PDT this evening for Central Coast-
     North Coast-Western Strait of Juan De Fuca.

     Red Flag Warning until 11 PM PDT Tuesday for West Slopes of the
     Central Cascades Generally above 1500 Feet-West Slopes of
     the North Cascades Generally above 1500 Feet.

PZ...None.

&&

$$