399
FXUS66 KSEW 300257
AFDSEW

Area Forecast Discussion
National Weather Service Seattle WA
757 PM PDT Wed May 29 2024

.SYNOPSIS...Convergence zone activity with embedded thunderstorms
are likely to persist into the evening hours before dissipating.
Weak high pressure will impact the region from the south for drier
and slightly warmer temperatures on Thursday and Friday.
Additional frontal systems and an increase in moisture is likely
to return early next week.

&&

.SHORT TERM /TONIGHT THROUGH SUNDAY/...Convergence zone showers
continue to occur along and just south of the I-90 corridor
through King County and drifting southward towards Pierce County.
The threat for thunderstorms has largely ended now that the sun
is setting and instability has waned across the region. Additional
showers are moving in along the coast, but are generally just
light rain at the time of this writing.

A shortwave ridge is expected Thursday and Friday ahead of the
next frontal system, but it is only expected to return the
temperatures to seasonally normal, upper 60s and low 70s. Some
shower activity associated with the next front may arrive at the
coast by Friday afternoon, but Puget Sound and the rest of the
interior will have to wait until early Saturday morning to see
that wave of precipitation arrive.

Kristell/LH

.LONG TERM /MONDAY THROUGH THURSDAY/...Long range cluster
analysis is in good agreement on troughing lingering in the area,
favoring cooler temperatures and increased precipitation. Sunday
through Tuesday will feature a parade of systems, some taking on
atmospheric river levels of moisture and high snow levels,
bringing up to 4 inches of rain on the windward slopes of the
Olympics and Cascades, amd over an inch of rain throughout much of
Puget Sound over those three days. While some may digress that
this is not the type of late spring weather most desire, receiving
moisture like this at this point in the year is incredibly
beneficial in providing some breathing room on fuel receptiveness
to fires. While it won`t nix the threat of a fire season
completely, the region is far better off with receiving this
moisture than not.

That tidbit aside, high temperatures through Wednesday will likely
only be in the upper 50s and low 60s. With ongoing precipitation
over three days, the Skokomish, Snohomish and Skykomish rivers
will need to be monitored as they are likely to rise into Action
stage flood levels by Monday and Tuesday.

For what its worth, and much further in the distance, it is worth
noting that in the 8-14 day outlook from the Climate Prediction
Center, there is a signal for a heat event centered over
California, but western Washington is in the slight risk of
excessive heat category. This is something that will be closely
watched and at this time, no projections on exact temperatures can
be made, but rather something to think about if you still need to
get air conditioning units put back in windows, etc.

Kristell

&&

.AVIATION...Generally VFR with convergence zone shower activity
lingering into the evening. High pressure will continue to build
inland tonight, allowing for some terminals to see MVFR ceilings in
the morning. Surface winds generally N/NW at 10 kt or less
decreasing overnight and shifting S/SE to 5 kt or less. Improving
conditions back to VFR by the late morning with winds generally
returning N/NW 5-12 kt.

KSEA...Convergence zone activity continuing to linger in the
evening, with ENE winds holding on driven by shower activity. Winds
will shift S/SE 5 to 8 kt after showers end for the night, with
models highlighting between 04z/06z. MVFR ceilings may develop
early/mid morning, but confidence is low. Conditions will improve as
the sun comes up and return to VFR with a wind shift to NW 5 to 9 kt
in the afternoon.

AL

&&

.MARINE...High pressure will continue to build inland tonight
through Friday, with a westerly push through the Strait of Juan de
Fuca tapering off in the morning Thursday. A series of fronts will
cross the region late Friday through the weekend and into early next
week, bringing potential for gusty winds and higher seas. SCA winds
may return Sunday or Monday through the Strait of Juan de Fuca,
while seas will remain between 4 and 7 ft through the weekend.
Tuesday will bring potential for seas to approach 10 ft or higher.

AL

&&

.SEW WATCHES/WARNINGS/ADVISORIES...
WA...None.
PZ...Small Craft Advisory until 2 AM PDT Thursday for Central U.S.
     Waters Strait Of Juan De Fuca-East Entrance U.S. Waters
     Strait Of Juan De Fuca.

&&

$$