900
FXUS66 KSEW 111651
AFDSEW

Area Forecast Discussion
National Weather Service Seattle WA
951 AM PDT Thu Jul 11 2024

.SYNOPSIS...An upper level ridge remains over Western Washington
through the weekend with continued low-level onshore flow. This
will maintain above normal temperatures, but still notably cooler
than the start of the week. Little change through the week ahead,
with no rain expected and only subtle variations in the strength
of the marine pushes each night.

&&

.SHORT TERM /TODAY THROUGH SATURDAY/... Forecast remains on track
this morning with no updates required. Previous discussion
follows.

Little change in the pattern for the next three days. Flat upper
level ridge over Western Washington with 500 mb heights in the mid
580 dms. Low level onshore flow of varying degrees through
Saturday. Stratus developing along the coast each evening/early
morning moving eastward in the early morning hours but at this
point it does not look like it will get east of the Puget Sound.
High temperatures in the mid 70s to mid 80s over the interior with
mid 60s to lower 70s for the coast. Lows with the onshore flow
will be cooler than the readings the last few days, in the 50s and
lower 60s.

.LONG TERM /SUNDAY THROUGH WEDNESDAY/...Small change in the
pattern Tuesday or Wednesday with the upper level flow becoming
southwesterly in response to an upper level trough well offshore.
500 mb heights stay in the lower to mid 580 dms range. The
operational GFS has a trough moving inland Monday but this
solution is somewhat of an outlier looking at the ensembles. The
ECMWF does not indicate a trough Monday. Low level flow remaining
onshore through the period. Persistence a good forecast with some
stratus developing along the coast each evening creeping inland
overnight but for the most part staying west of the Puget Sound.
High temperatures remaining in the mid 70s to mid 80s over the
interior and mid 60s to lower 70s along the coast. Felton

&&

.AVIATION...WSW flow aloft through the TAF period. Largely VFR for
most terminals today except for KHQM which will continue to have
MVFR cigs before clearing towards 19-21z as marine stratus burns
off. Low-level onshore flow looks to prevail with an additional
round of marine stratus possible overnight and into Thursday for
coastal terminals and maybe a couple inland as well. VFR mostly
elsewhere.

KSEA...VFR throughout the TAF period. Surface winds varying between
NE and NW around 5 to 10 kt.

McMillian/Mazurkiewicz

&&

.MARINE...A stout surface high well offshore will remain in place
into next week with lower pressure inland. Small craft advisories
are valid for the coastal waters today, and may need to be
extended well into Friday for the outer zones due to northerly
winds. Persistent onshore flow will remain in place into the
weekend with diurnally driven westerly pushes through the strait,
possibly accompanied with additional headlines.

Seas increasing to 6 to 8 ft today and nearing 10 ft tonight into
Friday for the outer coastal waters. Seas should subside into the
weekend.

McMillian/Mazurkiewicz

&&

.SEW WATCHES/WARNINGS/ADVISORIES...
WA...None.
PZ...Small Craft Advisory from 2 PM this afternoon to 5 AM PDT Friday
     for Central U.S. Waters Strait Of Juan De Fuca-East
     Entrance U.S. Waters Strait Of Juan De Fuca.

     Small Craft Advisory from 2 PM this afternoon to 2 AM PDT Friday
     for Coastal Waters From Cape Flattery To James Island Out
     10 Nm-Coastal Waters From James Island To Point Grenville
     Out 10 Nm-Coastal Waters From Point Grenville To Cape
     Shoalwater Out 10 Nm.

     Small Craft Advisory until 5 AM PDT Friday 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.

&&

$$