Brier Weather Station
Latitude N 47° 46' 49" Longitude W 122° 16' 48" Elevation 341 ft
476
FXUS66 KSEW 102211
AFDSEW
Area Forecast Discussion
National Weather Service Seattle WA
311 PM PDT Sun May 10 2026
.SYNOPSIS...
A weak system clipping the region has brought in an expansive
cumulus field with partly sunny skies. A warming trend is
expected through Tuesday. Thereafter, conditions become more
unsettled with a chance for isolated thunderstorms on Wednesday.
Cloudy and cooler conditions will persist through the end of the
week.
&&
.SHORT TERM /TONIGHT THROUGH TUESDAY NIGHT/...
The upper level clouds have largely moved out of area this
afternoon, with an expansive cumulus field over much of western
Washington. Temperatures thus far are in the 60s, with the
opportunity for a few more degrees of warming potential. High
pressure bumps back in early this week, with warming
temperatures through Tuesday. Tuesday looks to be on track for
the warmest temperatures this week, with widespread upper 70s to
mid 80s across the region. The warmest temperatures are
forecast to be in areas from south King County in through Mason
and Grays Harbor County. The Cascade valleys will also be well
into the 80s. These locations are giving a 50 to 70% chance of
reaching Moderate HeatRisk, which can impact the most sensitive
demographics-especially with limited access to cooling. Given
the pattern, minimum relative humidity values on Tuesday are
forecast to be between 25 to 30% in the Cascades and 35 to 40%
throughout much of Puget Sound. The winds, although light, seem
to be slightly northeasterly which could drive these RH
forecasts even lower. Overnight temperatures will be cool
enough to offset some of it being in the low to mid 50s. Relief
will be in short order as the pattern turns unsettled into the
second half of the week.
&&
.LONG TERM /WEDNESDAY THROUGH SUNDAY/...
The pattern becomes more unsettled Wednesday through the second
half of the week. A cutoff low offshore of the OR/CA border
amplifies and nudges the ridge off to the east. While the exact
track of that cutoff low is still carrying some uncertainty, it
does provide potentially favorable conditions for a few
thunderstorms Wednesday morning into early afternoon. Southerly
flow and an increase in CAPE could favor some orographically
enhanced storms in the southern WA Cascades and foothills. Right
now, it seems as though some of the ingredients are misaligned
with the generally necessary solar insolation of the day, but
this will be monitored as Wednesday approaches.
Broader troughing in the NE Pacific keeps onshore flow into
Washington for the rest of the week, allowing some weaker
systems to move in. Scattered showers could occur during this
timeframe but are unlikely to produce significant rains.
21
&&
.AVIATION...
Flow aloft between west to southwest throughout the TAF period. MVFR
cigs over Puget Sound terminals are gradually lifting to VFR this
afternoon. For tonight, mostly VFR again - can`t rule out areas of
MVFR stratus throughout the interior as the flow remains onshore.
Stratus along the coast will keep KHQM under MVFR/IFR into Monday
morning as well. Can`t rule out low stratus creeping into South
Sound (KOLM) as well. A slow burn off to widespread VFR by Monday
afternoon. Low-level onshore winds expected to become lighter
overnight before increasing out of the north on Monday afternoon.
KSEA...VFR so far this afternoon. However, areas of stratus are set
to redevelop this evening in moist onshore flow. The NBM has a 25-
30% chance of ceilings under 3,000 ft after 07z through 18z Monday.
If manifest, VFR is set to return by Monday afternoon. Surface winds
becoming variable this afternoon before turning more out of the
north around 00-02z.
41
&&
.MARINE...
Post-frontal onshore flow in the wake of a weak front. A westerly
push is currently brining SCAs through the Strait of Juan de Fuca
through tonight. Winds remain relatively light elsewhere and
primarily out of the north through the week. A potential system
midweek may bring another push through the strait. Additionally,
while low stratus is expected off the coast next couple mornings,
there is potential for some pockets of fog over the coastal waters
(especially in areas where the wind is calmer). Combined seas around
4-6 ft through the week (with a brief jump to 6-8 ft midweek).
41
&&
.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 Monday 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