939
FXUS66 KSEW 250937
AFDSEW

Area Forecast Discussion
National Weather Service Seattle WA
237 AM PDT Tue Jun 25 2024

.SYNOPSIS...High pressure aloft continues to build over the
region, maintaining warmer and dry conditions through Tuesday. The
next upper trough crosses the area Wednesday and Thursday bringing
a return of showers and cooler temperatures. Expect a similar
pattern late in the week with a brief warm up alternating with
weak passing disturbances.

&&

.SHORT TERM /TODAY THROUGH THURSDAY/...High pressure builds over
the Pac NW today for a brief warm-up - temps reaching the upper
70s to lower 80s in the interior. The coast will be cooler and in
the 60s with NW winds.

Wednesday will be cooler and cloudier as the ridge pushes east and
a trough moves in from the west. Temperatures on Wednesday will be
in the 60s to lower 70s - close to average. We`ll also see showers
with the trough and the coast may see 0.25" or so through the day.
Post-frontal onshore flow increases Wednesday night with a
convergence zone setting up over Snohomish and King counties.
There is also a slight chance of thunderstorms in the North
Cascades where instability is the greatest.

The trough moves east of the Cascades on Thursday but we`re still
under moderate onshore flow with more cool and wet weather
(especially in the interior and Cascades). Temperatures will dip
again with highs only in the 60s. 33

.LONG TERM /FRIDAY THROUGH MONDAY/...High pressure rebuilds over
the region Friday and Saturday for a return of dry and mild
weather (temps closer to average). West to SW flow returns
Saturday night and Sunday with another trough over the West.
There`s not as much moisture attached to this system (compared to
Wednesday-Thursday) but we should still see measurable rain
across most areas. Moving forward, we`re stuck in zonal, onshore
flow, into early next week. There`s a chance of showers along the
coast and in the mountains with near normal temperatures. 33

&&

.AVIATION...Zonal flow turning more south/southwesterly this
morning as weak ridging builds over W WA, with onshore flow
continuing in the lower levels. VFR early this morning will
dominate throughout the rest of the day as high pressure builds
over the region. N/NE winds generally around 5 to 10 knots,
turning more northwesterly late in the afternoon.

KSEA...VFR conditions this morning will continue throughout the
remainder of the day. North winds 8 to 12 knots this morning will
gradually ease into the afternoon and turn northwesterly, around
4 to 8 knots.

Maz

&&

.MARINE...High pressure situated offshore will help influence
lower pressure inland, with relative onshore flow throughout the
next several days. Diurnal pushes through the Strait of Juan De
Fuca are possible each of the days that could result in Small
Craft Advisories at times, with general benign conditions over
the coastal waters. A frontal system will push through the area
waters on Wednesday, with elevated southerly winds, but latest
guidance shows winds to be under any criteria thresholds for now.

Coastal seas this morning have been hovering around 4 to 6 feet
and generally will maintain this height through midweek and into
the weekend.

Maz

&&

.SEW WATCHES/WARNINGS/ADVISORIES...
WA...None.
PZ...None.
&&

$$