Brier Weather Station
Latitude N 47° 46' 49" Longitude W 122° 16' 48" Elevation 341 ft
695
FXUS66 KSEW 190856
AFDSEW
Area Forecast Discussion
National Weather Service Seattle WA
156 AM PDT Sun Apr 19 2026
.SYNOPSIS...
Mostly dry and mild conditions will continue into early next
week, before chances for precipitation increase across western
Washington through the middle of the week. Drying and warming
conditions are favored to return by next weekend.
&&
.SHORT TERM /TODAY THROUGH TUESDAY/...
Southerly flow aloft will develop over western Washington today
as a low pressure system drops southward along the Pacific
Coast. This will allow for temperatures to continue on a warming
trend, warming several degrees from yesterday. Most lowland
locations away from water will see highs in the low to mid 70s,
with some areas along the Cascade Foothills nearing 80 degrees.
By Monday, split flow will develop aloft as the low pressure
system moves southward towards the California Coast. This will
allow for steady conditions on Monday across western Washington,
with temperatures once again peaking in the low to mid 70s
across much of the lowlands and in the 60s along coastlines. As
the low begins to push inland, wrap around moisture may generate
light shower activity over the western Cascades late monday.
The upper level low will begin to shift inland overnight Monday
into Tuesday, which will bring increasing chances for rain
across western Washington, particularly for areas south and west
of the Puget Sound. As moisture continues to be advected
northward, chances for widespread rain increase across the
region. Unstable conditions may produce a few lightning strikes
over the Cascades on Tuesday, with cooler temperatures peaking
in the upper 50s to low 60s.
&&
.LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/...
Chances for widespread precipitation continue on Wednesday as
the low pressure system to the south slowly moves inland. By
Thursday, the system will be over the Intermountain West,
pulling most of the associated moisture west of the Cascades.
Ensembles and operational models remain in good agreement on
Friday and heading into the weekend, with potential for warm and
dry conditions to return.
15
&&
.AVIATION...
A ridge of high pressure will continue to shift eastward today as an
upper level low remains off the coast, sinking south. This will
result in southerly flow aloft with occasional shifting to the
southeast this afternoon and evening. Surface winds at most
terminals have become light and variable and will remain that way
into the early morning. Obs showing winds with a consistent
direction are mostly northerly. As winds increase to 4-8 kts by mid-
morning, most terminals will remain north to northeasterly.
VFR conditions area-wide this early morning and expected to remain
that way. The aforementioned low pressure off the coast will keep
high level clouds in place overhead, but should not have any
significant impact.
KSEA...VFR conditions will continue throughout the TAF period.
Northerly winds 4-8 kts for much of the forecast although some
shifts to the northeast are expected, especially this evening and
tonight.
18
&&
.MARINE...
Low pressure will track south over the offshore waters today with
offshore flow over western WA into Monday. Onshore flow resumes on
Tuesday as the low weakens further then shifts inland. Seas
generally 4-6 ft for much of the day, building slightly to 5-7 ft
tonight. A more significant increase to seas is expected Wednesday,
where waves will build to over 10 ft in the outer coastal waters.
18
&&
.HYDROLOGY...
River flooding is not expected over the next 7 days.
&&
.SEW WATCHES/WARNINGS/ADVISORIES...
WA...None.
PZ...None.
&&
$$
NWS SEW Office Area Forecast Discussion