943
FXUS66 KSEW 110312
AFDSEW

Area Forecast Discussion
National Weather Service Seattle WA
812 PM PDT Wed Jul 10 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 /TONIGHT THROUGH SATURDAY/...No significant changes
made to the forecast this evening. The previous discussion can be
found below along with updates to the aviation and marine
discussions:

A much cooler afternoon across most of the area today than this
time yesterday, with temperatures generally running 5 to 10
degrees cooler than 24 hours ago. The overall pattern will not
change too much through the remainder of the week with high
pressure in place over the region and light onshore flow
maintaining some cloud cover along the coast, into the lower
Chehalis valley, and also through the Strait of Juan de Fuca. This
will remain a somewhat shallow push though - enough to bring the
cooling marine influence progressively into the interior, but
unlikely to bring stratus to fill the interior. This will bring
overnight lows back down into the 50s and closer to seasonal
normals, while abundant sunshine will maintain highs in the 80s.

.LONG TERM /SUNDAY THROUGH WEDNESDAY/...Strong ensemble agreement
to support very little impactful changes to the weather pattern in
the first half of next week. Expect continued influence from high
pressure aloft with onshore low-level flow persisting through the
week. This will bring additional rounds of stratus pushes in the
morning and plenty of afternoon sun for most, along with high
temperatures generally in the 80s through the interior. A weak
disturbance around Monday or Tuesday may be responsible for a
slightly deeper push of marine stratus and favor temperatures more
in the lower 80s as opposed to mid to upper 80s, but that`s really
the biggest change in the day to day pattern through the next
week.

&&

.AVIATION...Upper level ridging over the central US with weak
troughing over the eastern Pacific will keep SW flow in place aloft
into tonight before becoming more zonal overnight. Evening hours
bring more northwesterly winds to the region with speeds generally
8-10 kts, before becoming light and variable overnight.
Exceptions will be HQM and CLM, where westerly marine push will be
dominant direction and BLI, where winds will remain southerly
throughout the TAF period.

Widespread VFR conditions in place and are expected to remain that
way for most sites through the majority of the TAF period. Onshore
push overnight may allow for MVFR to IFR conditions impact HQM and
PWT as marine stratus seep inland. PWT will likely see skies improve
first...by around 18Z Thursday while HQM will likely wait to break
out in the early to mid afternoon hours.

KSEA...VFR throughout the TAF period. Above surface wind discussion
applies.

33/18

&&

.MARINE...Surface ridge over the NE Pacific will strengthen
just off the coastal waters through the week. A gradual increase in
onshore flow is expected over the area...resulting in gales forecast
for the central and eastern Strait. Forecast also suggesting SCA
level winds emerging in the outer coastal waters overnight...however
this might be slightly overdone. Have capped winds there at 15 to
20 kts with potential to reach SCA during the day tomorrow. Will
advise future shifts to monitor, as an SCA for this area is not
too far out of the question. Persistent onshore flow will remain
in place into the weekend with diurnally driven westerly pushes
through the Strait, possibly accompanied with additional
headlines.

Seas generally 4 to 6 ft before increasing to 6 to 8 ft Thursday and
nearing 10 ft by Friday for the outer coastal waters.

33/18

&&

.SEW WATCHES/WARNINGS/ADVISORIES...
WA...None.
PZ...Gale Warning until 5 AM PDT Thursday for Central U.S. Waters
     Strait Of Juan De Fuca-East Entrance U.S. Waters Strait Of
     Juan De Fuca.

&&

$$