587
FXUS66 KSEW 270953
AFDSEW

Area Forecast Discussion
National Weather Service Seattle WA
253 AM PDT Thu Jun 27 2024

.SYNOPSIS...Cooler and wetter weather continue today with an upper
low over the region. Warmer and drier conditions set in for
Friday into early Saturday, but another disturbance will bring
showers again late Saturday into Sunday. A few showers linger into
Monday then mainly dry and seasonable weather toward midweek.

&&

.SHORT TERM /TODAY THROUGH SATURDAY/...Cool and wet weather
continues across western WA today with an upper level low over the
Pac NW. We`re still under moderate onshore flow today with ongoing
showers, especially over the Cascades. Showers with the
convergence zone will likely shift south and stall over the
King/Snohomish line this morning and afternoon. Temperature-wise,
highs will only track in the 60s today (or around 5 degrees cooler
than average). Showers will gradually taper down overnight as the
upper low departs E/NE toward southern Alberta/Saskatchewan.

Weak high pressure brings drier and slightly warmer weather to the
region on Friday. Temperatures will reach the lower to mid 70s in
the interior and closer to average. The coast will remain in the
60s with NW flow.

The next incoming frontal system will stall offshore on Saturday
while a ridge builds over the Rockies. Western WA is looking
mainly dry through the day with a few light showers coast and
mountains. 33

.LONG TERM /SUNDAY THROUGH WEDNESDAY/...Troughing over the Pac NW
brings a chance of showers on Sunday (coast and mountains) with
isolated shower coverage in the interior. The air mass is slightly
unstable and there`s also a slight chance of thunderstorms in the
North Cascades. Moving forward, broad high pressure over the
eastern Pacific extends through the West and keeps much of the
Pac NW dry. The flow is onshore through early-mid week with
temperatures close to normal. 33

&&

.AVIATION...Westerly/northwesterly flow aloft this morning as a
upper level trough moves eastward through W WA. Recent radar
imagery shows scattered showers throughout the area this morning,
with a mixed bag of ceilings anywhere from LIFR to VFR.
Generally, a more consolidated layer of MVFR will be likely
throughout most of the morning and afternoon as rain showers
persist thru the day. Localized pockets of IFR to LIFR conditions
will continue to be possible for terminals in heavier showers.
Latest guidance suggests a convergence zone to develop across
northern King and Snohomish counties this morning through this
afternoon, so could definitely see some lower ceilings persisting
at KPAE into the evening (IFR/LIFR)

S/SW winds this morning around 8 to 12 knots in the interior will
start to ease after 22z, decreasing to around 4 to 8 knots.

KSEA...MVFR conditions this morning as showers continue to push
through the region. MVFR will likely continue through the
afternoon, with S/SW winds 8 to 12 knots. Winds will gradually
decrease after 00z. Guidance suggests a convergence zone to
develop this afternoon and evening near the King/Snohomish county
line.. with the possibility of winds turning northerly 03z-06z if
it moves southward near the terminal.

Maz

&&

.MARINE...A exiting frontal system over the area will lead to
increased onshore flow this afternoon over the area waters, with
small craft westerly winds through the Strait of Juan De Fuca.
Weak high pressure looks to build into the area through Friday,
with additional systems likely into the weekend. Additional
pushes down the Strait are possible through early next week,
although at this time winds look to be below any criteria.

Coastal seas around 4 to 6 feet this morning will continue through
this weekend and into the first half of next week.

Maz

&&

.SEW WATCHES/WARNINGS/ADVISORIES...
WA...None.
PZ...Small Craft Advisory from 8 AM this morning to 11 PM PDT this
     evening for Central U.S. Waters Strait Of Juan De Fuca-East
     Entrance U.S. Waters Strait Of Juan De Fuca.

&&

$$