Brier Weather Station
Latitude N 47° 46' 49" Longitude W 122° 16' 48" Elevation 341 ft
149
FXUS66 KSEW 021026
AFDSEW
Area Forecast Discussion
National Weather Service Seattle WA
326 AM PDT Thu Apr 2 2026
.SYNOPSIS...
Upper level low over the area will move east today. Weak upper
level ridge trying to build tonight and Friday with a system
moving by to the north Friday. Upper level ridge strengthening
Friday night and remaining in place into early next week. Upper
level trough moving by to the north Tuesday with an upper level
low approaching the Oregon coast.
&&
.SHORT TERM /TODAY THROUGH SATURDAY/...
Satellite imagery shows broad upper level low over the Pacific
Northwest. Showers rotating around the low along the coast and
Southwest Interior. Doppler radar shows convergence zone right
on top of the radar on Camano Island. Temperatures at 3 am/10z
were mostly in the lower to mid 40s. Olympia is the cool spot
with 35 degrees.
Upper level low slowly moving east today. Moisture wrapping
around the low moving into Western Washington keeping showers in
the forecast. Snow levels 2500 to 3000 feet for snow in all the
passes except Snoqualmie. An additional 4 to 8 inches of snow
possible today in the Cascades with most of the snow coming in
the morning. The advisory will remain in effect through 11 am.
Convergence zone over Island County will drift east and dissipate
this morning. Highs in the lower to mid 50s.
Low well to the east tonight with the upper level flow becoming
northwesterly. Upper level ridge trying to build into the area.
Showers coming to an end in the lowlands but lingering in the
mountains in the evening hours. Plenty of moisture left over
Western Washington keeping skies mostly cloudy. This will
prevent lows from getting too cold Friday morning. The colder
locations will be in the mid 30s while a majority of the area
will be a couple of degrees either side of 40.
Weak system riding over the flat upper level ridge Friday for a
chance of showers along the coast and over the northern
portions. Mostly cloudy for the remainder of the area. Highs
warming up getting closer to normal, in the mid 50s.
Upper level ridge strengthening Friday night and Saturday with
the ridge axis right along the coast. Clearing skies will allow
temperatures to drop into the 30s Saturday morning. Warming
trend continuing with highs in the upper 50s to mid 60s. Felton
&&
.LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/...
Upper level ridge remaining over Western Washington into Monday.
Low level offshore flow Sunday becoming light Monday. Trough
riding by to the north Tuesday with an upper level low
approaching the Oregon coast from the southwest. Slight chance
moisture spinning out of this low makes it to Western
Washington. A little bit better chance of showers Wednesday as
the low moves closer to the coast.
Warming trend through the weekend peaking Monday with highs in
the 60s and lower 70s. The forecast high of 67 degrees Monday in
Seattle would be the warmest day since October 7th. Highs
cooling Tuesday and Wednesday back mostly into the mid and
upper 50s. Lows in the lower to mid 40s cooling to the mid 30s
to lower 40s Wednesday morning.
&&
.AVIATION...
Flow aloft will become more north-northwesterly today as an
upper trough axis shifts east of the area and weak upper
ridging starts to build into the region. Conditions at the area
terminals this morning are primarily VFR to MVFR with showers
continuing across western WA in the post-frontal airmass.
Overall, expect more widespread MVFR conditions, and even
pockets of IFR, to develop across the area through the morning
hours, particularly between 10Z to 19Z. Conditions will slowly
improve towards low-end VFR by midday, though could see MVFR
conditions continue into the afternoon for terminals across
central Puget Sound, as well as portions of the Olympic Peninsula.
Showers will slowly taper and become more confined to the
mountains by the afternoon hours. However, hi-res guidance does
indicate some weak convergence zone shower activity developing
across the central Sound by this afternoon and persisting into
this evening. South/southwest surface winds will persist
throughout the day, increasing to 10-15 kt by this afternoon,
before subsiding to 5-10 kt again by late tonight.
KSEA...MVFR ceilings at the terminal early this morning. There
remains a low chance, around 20%, of IFR cigs developing between
12 to 15Z. Otherwise, expect ceilings to lift back towards high-
end MVFR to low-end VFR by mid afternoon. Southwesterly surface
winds will remain elevated between 8-12 kt today, before easing
back to 5-10 kt by tonight.
14
&&
.MARINE...
Breezy post-frontal onshore flow will continue through the
morning hours today, before easing. High pressure will then
build back into the area waters today and will remain situated
over the region through the weekend. Periods of northerly or
weak offshore flow will develop at times Saturday and Sunday as
a thermally induced trough expands northward from the Oregon
coast. Onshore flow will then return by Monday as a weak system
passes to the north of the waters. The next disturbance looks
to move into the area waters by Tuesday.
Seas will hover between 8-12 ft across the area waters today,
before gradually subsiding back towards 6-8 ft by Friday and
4-6 ft over the weekend. Seas will increase towards 6-9 ft again
by Tuesday in response to a disturbance moving across the area
waters.
14
&&
.HYDROLOGY...
No river flooding in the next 7 days.
With the low snow levels rivers did not respond much to the
rain Wednesday. No records were set but it was the 2nd wettest
April 1st on record in Seattle and Bellingham. The 0.81 inches
at Bellingham was just 0.09 inches of the record 0.90 inches
and nearly 30 percent of the normal rainfall for the month of
April. Bellingham yearly rain total now 14.32 inches. The
wettest start to the year through April 1st since 1984. Felton
&&
.SEW WATCHES/WARNINGS/ADVISORIES...
WA...Winter Weather Advisory until 11 AM PDT this morning for
Cascades of Pierce and Lewis Counties-Cascades of
Snohomish and Northern King Counties-Cascades of Southern
King County-Cascades of Whatcom and Skagit Counties.
PZ...Small Craft Advisory until 5 PM PDT this afternoon for Coastal
Waters From Cape Flattery To James Island 10 To 60 Nm-
Coastal Waters From Cape Flattery To James Island Out 10
Nm-Coastal Waters From James Island To Point Grenville 10
To 60 Nm-Coastal Waters From James Island To Point
Grenville Out 10 Nm-Coastal Waters From Point Grenville
To Cape Shoalwater 10 To 60 Nm-Coastal Waters From Point
Grenville To Cape Shoalwater Out 10 Nm-Grays Harbor Bar.
Small Craft Advisory until 11 AM PDT this morning for Central
U.S. Waters Strait Of Juan De Fuca-East Entrance U.S.
Waters Strait Of Juan De Fuca.
&&
$$
NWS SEW Office Area Forecast Discussion