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000
FXUS66 KSEW 130958
AFDSEW

Area Forecast Discussion
National Weather Service Seattle WA
258 AM PDT Sat Apr 13 2024

.SYNOPSIS...Weak high pressure overhead through the weekend
bringing warmer and drier conditions. Upper-level troughing
returns on Monday with showers and cooler temps. But, signs are
pointing towards more ridging later in with the possibility for more
warm and dry weather.


&&

.SHORT TERM /TODAY THROUGH MONDAY/...Welcome to the weekend,
folks. We`re in store for benign conditions here across western
Washington. Current 500mb analysis shows quasi-zonal flow over
much of BC and an upper-low spinning just off the CA coast. In
between, there`s weak upper-level ridging nosing into our neck of
the woods here over the PNW. Today`s weather will feature sunny
skies and above average temperatures due to large scale subsidence
provided by aforementioned ridging. Highs are forecast to top out
in the mid 50s to upper 60s. The trend will last into Sunday as
well however, strong onshore flow looks to bring cooler
temperatures particularly along the coast, Olympic Peninsula and
surrounding areas but still just above average for mid-April.
The westerly surge will bring gusty conditions through the
Strait of Juan de Fuca also. Gusts up to 30-35 mph are possible
for locations such as Whidbey Island on Sunday evening. Lows will
fall to the lower to mid 40s for both nights.

The pattern looks to change on Monday because of course, Monday.
Upper-level troughing will return along with widespread showers
and cooler conditions. Temperatures across the interior will drop
8-10 degrees Sunday to Monday. Lower snow levels are in the offing
as well with values hovering around 2,000 ft by Monday night. A
couple inches of snow can`t be ruled out for the passes during
this time.


.LONG TERM /TUESDAY THROUGH FRIDAY/... A few showers are slated to
remain on Tuesday but things may trend drier again towards midweek.
Deterministic guidance continues to hint at a ridge amplifying
around Wednesday-Thursday and lasting towards the weekend. But,
questions remain on its exact location and intensity. Nevertheless,
the brief cool down to start the next may not last too long as
temps could possibly top out near 70 F by Friday.

McMillian

&&

.AVIATION...VFR with SCT high clouds as drier air moving into the
region this morning. Winds generally from the north 3 to 6 kt,
increasing to 8 to 12 kt this afternoon.

KSEA...VFR with mostly clear skies. Northerly flow 4 to 6 kt this
morning will increase to 8 to 12 kt with occasional gusts up to 20
kt by the afternoon.

AL

&&

.MARINE...High pressure will continue to build eastward towards the
region this weekend and into the beginning of next week. As a
result, northwesterly winds will slowly build through the course of
this weekend. A Small Craft Advisory will continue Saturday for the
coastal waters 10-60 NM out. The pressure gradient looks to sharply
increase on Sunday, which will develop stronger winds through the
northern portions of the coastal waters, as well a solid push
through the Strait of Juan de Fuca, which will likely reach Small
Craft Advisory levels, with gusts reaching up to gale force
possible. Winds look to ease into next week as the high pressure
system looks to center itself over the region.

Seas 7 to 9 ft will gently rise Sunday to 9 to 12 ft, with the
highest waves over the northern coastal waters up towards Vancouver
Island. With the persistent northwesterly winds, waves will become
steep on Sunday with heights 9 to 12 ft with a 9 to 10 second
period. This sea state will likely persist into Monday, through
could linger as late as early Tuesday.

LH/AL


&&

.HYDROLOGY...No river flooding is expected through the next seven
days.


&&

.SEW WATCHES/WARNINGS/ADVISORIES...
WA...None.
PZ...Small Craft Advisory until 11 PM PDT this evening for Coastal
     Waters From Cape Flattery To James Island 10 To 60 Nm-
     Coastal Waters From James Island To Point Grenville 10 To
     60 Nm-Coastal Waters From Point Grenville To Cape
     Shoalwater 10 To 60 Nm.

&&

$$