Brier Weather Station
Latitude N 47° 46' 49" Longitude W 122° 16' 48" Elevation 341 ft
896
FXUS66 KSEW 110842
AFDSEW
Area Forecast Discussion
National Weather Service Seattle WA
142 AM PDT Mon May 11 2026
.SYNOPSIS...
A ridge of high pressure will produce a warming trend through
Tuesday. A transition to onshore flow and cooler temperatures
will take place on Wednesday along with a chance of some
precipitation. Cooler and unsettled conditions are expected into
the upcoming weekend as a trough of low pressure over the
Northeast Pacific sends a series of weak frontal systems across
the area.
&&
.SHORT TERM /TODAY THROUGH WEDNESDAY/...
A ridge of high pressure aloft will rebuild into the area today
with low level flow turning northerly. After areas of morning
clouds, mostly sunny skies are expected today along with
modestly warmer temperatures. The low level turns offshore
tonight as thermally induced low pressure expands northward
along the coast. Temperatures will warm further on Tuesday with
most of the region getting into the 70s and lower/mid 80s. A
few spots across the interior will briefly reach moderate
heatrisk criteria. The low level flow turns onshore late in the
day on Tuesday...with a cooling sea breeze for the coast.
The forecast Tuesday night and Wednesday remains something of a
a conundrum. A closed off and negatively tilted upper low will
approach the coast somewhere between far northern California
and Oregon. Model solutions remains split in their handling of
this. Of note, the 00Z ECMWF deterministic run and many of it`s
ensembles bring the low further north putting Western
Washington squarely in the crosshairs of some elevated
instability and diffluence aloft. Should this occur, we could be
talking about some nocturnal convection popping up Tuesday
night into early Wednesday morning. The GFS suite of ensembles
are less enthused about this scenario, but about half of them do
generate some precip on Wednesday. Needless to say, uncertainty
in the Wednesday forecast remains high, but cooler temperatures
and a chance of showers or isolated thunderstorms looks like a
safe forecast. Stay tuned.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/...
A mean upper trough position takes up residence over the
Northeast Pacific for the second half of the week. This will
lead to cooler conditions and some light precip at times
Thursday into Saturday. There`s general agreement that weak
upper ridging will attempt to make some inroads late in the
weekend for perhaps drier conditions and temperatures recovering
to around seasonal normals.
27
&&
.AVIATION...
Northwest flow aloft behind a trough will become more
neutral during the day, returning to southwest as a ridge passes
over the region. Satellite is tracking a few areas of lower stratus
this morning. The densest areas are along the coast and in the
mountains, with a few patches in the interior beginning to fill in.
Majority of the ceilings will be in the VFR/MVFR category this
morning, with a chance of IFR/LIFR along the coast/southwest
interior briefly this morning. The ridge overhead will result in low
clouds clearing by roughly 15-19Z late this morning with clear
skies. NE winds 3-6 kt this morning will turn to the north 6-12 kt
today, becoming NE again under 5 kt tonight. Chance of low cigs/vis
Tuesday morning remains confined to the coast.
KSEA...Pockets of stratus in and around the terminal this morning
will keep at least a chance of MVFR going through late morning, with
clearing taking place shortly after (VFR). NE winds around or less
than 5 kt will turn to the north 6-12 kt during the day, decreasing
to under 5 kt from the northeast tonight.
HPR
&&
.MARINE...
A post-front push through the Strait of Juan de Fuca will
weaken early this morning as high pressure builds again in the
eastern pacific via a ridge. Coastal waters may have a couple
pockets of fog underneath the stratus early this morning. There
is also a thermal trough expected for Tuesday that may bring a
brief period of offshore flow. Models have a trough/front
passing through midweek, with a 40% chance of showers over the
interior waters. While winds for most waters will remain light
through the week, there will continue to be pushes of winds
(likely greater than 20 kt) through the Strait of Juan de Fuca
at times - particularly Wednesday and Friday. Seas will hold
around 4-6 ft through the week, with a brief jump up to 6-8 ft
midweek.
HPR
&&
.HYDROLOGY...
The daily hydrology discussion has ended until the start of the
next rainy season; it will only be updated during this time as
needed.
&&
.SEW WATCHES/WARNINGS/ADVISORIES...
WA...None.
PZ...Small Craft Advisory until 3 AM PDT early 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