153
FXUS66 KSEW 262159
AFDSEW

Area Forecast Discussion
National Weather Service Seattle WA
259 PM PDT Sun May 26 2024

.SYNOPSIS...Cooler and showery conditions will continue across
western Washington today as a frontal system brushes the region.
Upper level ridging will then gradually begin to build east of
the area Monday, allowing for temperatures to warm. Upper level
troughing over the northeastern Pacific will continue to influence
Washington, with the next frontal system poised to move across
the region on Tuesday. Drier and warmer conditions will be
possible late in the week as upper ridging builds offshore.

&&

.SHORT TERM /TONIGHT THROUGH WEDNESDAY/...Per recent radar
imagery, showers continue to move through western Washington as a
frontal system brushes by the region. Most of the showers are
concentrated in more of the Northern Interior, the Cascades, and
coastal areas. Showers will gradually decrease in coverage later
this evening into tonight, with some showers lingering in the
Cascades and the interior lowlands remaining mostly dry.
Afternoon high temperatures will continue to be below normal, in
the mid to upper 50s.

An upper level ridge too start to build eastward of our region
through Monday, while troughing offshore will continue to keep an
influence over western Washington. Temperatures will warm slightly
to near normal, in the upper 60s. Locations near the coast and
other bodies of water will have high temps stay in the mid to
upper 50s. Shower chances will start to increase throughout Monday
evening and into Tuesday as an approaching frontal system and
trough nudges closer to western Washington. The associated
frontal system and trough will spread showers throughout majority
of the area into Tuesday evening, with high temperatures dipping
back down to below average, in the upper 50s.

The aforementioned trough axis will move over western Washington
on Wednesday, allowing for showers to stay around the area. Along
with showers, cooler air aloft might promote some instability that
could lead to a few convective showers over the interior
Wednesday afternoon. If any convective showers do develop, the
primary threats would be lightning and small hail. Although
instability values does not look overly impressive, thunderstorm
chances look to be around 20-25% over region.

.LONG TERM /THURSDAY THROUGH SUNDAY/...Showers will decrease in
coverage heading into Thursday as most ensemble guidance agree on
the trough exiting our area and an upper level ridge building
off in the Pacific. Cluster and ensemble based guidance show conditions
beginning to dry our and warm up throughout the end of the week
and into the weekend.

Mazurkiewicz

&&

.AVIATION...A warm front will shift north then stall over
southern B.C. tonight with showers mainly over the north coast and
north Cascades. Ceilings are a mixed bag with pockets of MVFR
conditions. The trend is for improving conditions this evening
with most terminals in VFR range. Expect dry weather and VFR
moving further into Monday. 33

KSEA...Showers shifting north of the terminal this afternoon with
VFR conditions prevailing. S/SW wind around 10 kt. Dry on Monday
with VFR. 33

&&

.MARINE...A warm front will shift north then stall over southern
B.C. tonight. Weak high pressure will shift inland on Monday with
generally light winds over the waters. The next Pacific frontal
system will move inland on Tuesday, followed by onshore flow
Tuesday night and Wednesday (Small Craft Advisory winds are
possible through the Strait of Juan de Fuca). The flow remains
onshore through the end of the week with strong high pressure over
the NE Pacific. 33

&&

.SEW WATCHES/WARNINGS/ADVISORIES...
WA...None.
PZ...None.
&&

$$