Brier Weather Station
Latitude N 47° 46' 49" Longitude W 122° 16' 48" Elevation 341 ft
187
FXUS66 KSEW 131543
AFDSEW
Area Forecast Discussion
National Weather Service Seattle WA
843 AM PDT Sun Sep 13 2026
.SYNOPSIS...
An upper-low will continue to bring rain and showers to the area
today before exiting later this evening. More benign conditions
Monday before additional troughing returns on Tuesday with
another shot of showers. Drier and warmer midweek onward as
upper-level ridging builds.
&&
.SHORT TERM /TODAY THROUGH TUESDAY/...
The upper-low center is currently along the Oregon coast as it
continues to spin rain and showers across W WA. Rain has largely
ended along the coast, but will continue across the interior of
western Washington through this afternoon, and through the
mountains overnight. The main swath of precipitation is favored
to be generally Snohomish County southward. An additional
0.50-1.50" of rainfall is possible for the Cascades with
0.25-0.50" throughout the Puget Sound lowlands. Elsewhere should
see generally less than 0.25" of rainfall. Winds will also
increase today as the system departs, but remain mostly benign
with peak gusts in the 20-30 mph range.
Expect drier conditions on Monday. The aforementioned upper-low
will be well east of the area, near the northern Great Plains
by Monday evening. We`ll be left in a regime of northwesterly
flow aloft as a stout upper-ridge positions over the Gulf of
Alaska. Models are showing the development of an additional
upper-low within this flow regime on Tuesday with a possible
return of showers. High temperatures on Sunday mainly in the mid
60s before warming into the upper 60s to near 70 F. Overnight
lows in the 50s with a few 40s possible.
&&
.LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/...
Models have an upper-level ridge over the northeast Pacific
moving over the Pacific Northwest through the end of the week,
bringing a drier, sunnier, and warmer pattern. A surface thermal
trough will develop, allowing winds to turn lightly offshore.
Highs look to rise by Thursday into the upper 70s to low 80s.
&&
.AVIATION...
Upper level low over the North Oregon Cascades
early this morning will move northeast ending up over Western
Montana by late tonight. High pressure building offshore behind
the low. Northeasterly flow aloft this morning becoming
northerly this afternoon and northwesterly tonight. In the lower
levels, increasing onshore flow this afternoon and tonight.
Mostly IFR to MVFR this morning in rain. Ceilings lifting to
VFR late this afternoon and evening. However, MVFR ceilings
developing tonight near the East Entrance of the Strait of Juan
de Fuca with a convergence zone. The zone will remain over
Snohomish County into Monday morning.
KSEA...Ceilings this morning in IFR to MVFR range with rain.
Ceilings improving this afternoon to VFR, then back down to
MVFR overnight and into Monday morning. Southeast wind 4 to 8
knots becoming southwest 10 to 15 knots this afternoon. Winds
easing to 6 to 10 knots early Monday morning. 33/Felton
&&
.MARINE...
Increasing onshore flow today and tonight with Small
Craft Advisory winds over Puget Sound/Hood Canal, Northern
Inland Waters and the strait. High pressure will build over the
area Monday and remain through Wednesday. A thermally induced
surface trough will move up the coastline Wednesday night then
shift inland Thursday afternoon.
Seas remaining in the 3 to 5 foot range over the inner coastal
waters and mostly 4 to 6 feet over the outer coastal waters.
33/Felton
&&
.SEW WATCHES/WARNINGS/ADVISORIES...
WA...None.
PZ...Small Craft Advisory from 6 PM this evening to 5 AM PDT Monday
for Central U.S. Waters Strait Of Juan De Fuca-East
Entrance U.S. Waters Strait Of Juan De Fuca-Northern
Inland Waters Including The San Juan Islands-Puget Sound
and Hood Canal.
&&
$$
NWS SEW Office Area Forecast Discussion