Brier Weather Station
Latitude N 47° 46' 49" Longitude W 122° 16' 48" Elevation 341 ft
529
FXUS66 KSEW 032103
AFDSEW
Area Forecast Discussion
National Weather Service Seattle WA
203 PM PDT Thu Sep 3 2026
.SYNOPSIS...
A low pressure system will remain situated over the Pacific
Northwest through the weekend, maintaining cooler temperatures
and daily chances for light showers and isolated thunderstorms.
Split flow is favored to develop early next week, bringing drier
and slightly warmer conditions. Chances for additional rain
increase towards the end of next week with the potential arrival
of another trough.
&&
.SHORT TERM /TONIGHT THROUGH SATURDAY NIGHT/...
A low pressure system that brought fall-like conditions to
western Washington will continue to influence the weather into
the weekend, bringing daily chances for scattered showers and
isolated thunderstorms. The storm system will continue to drift
southwards today, maintaining chances for showers and
thunderstorms area-wide today. Showers will continue to develop
over the Cascades and southern interior through the afternoon,
drifting northwestward. The low pressure system will continue to
shift southward through the evening, putting an end to ongoing
convection as the environment becomes more stable.
More of the same is expected on Friday as the upper low slowly
shifts inland. By Saturday, the low shifts northward, advecting
wrap-around moisture into the area, bringing more widespread
chances for showers and isolated thunderstorms. Temperatures
through the short-term will remain below normal, with highs in
the upper 60s to low 70s each day.
&&
.LONG TERM /SUNDAY THROUGH THURSDAY/...
Forecast confidence decreases into next week, with some models
keeping the low pressure system over us into Monday while some
bring weak ridging over the area. While coverage decreases
Sunday and especially into Monday, continued shower and
thunderstorm activity remains possible alongside cooler
temperatures. Models come into better agreement by Tuesday with
split flow developing aloft, which would allow conditions to
warm up and dry out with morning fog and low stratus. However,
uncertainty remains over how long that would last, with another
wet weather system on track to enter the region by next weekend.
15
&&
.AVIATION...
South to southeasterly flow as an upper level low continues to
dig southward along western Washington`s coast. Mostly VFR
conditions this afternoon with some localized spots of MVFR
ceilings due to lingering scattered showers. Latest model
guidance continues to a suggest a 10-20% chance of a
thunderstorm across the area later this afternoon. Generally,
confidence is low of any thunderstorm impacting any terminal as
instability remains low. Overall, widespread VFR should
continue throughout the evening, can could see brief MVFR at
times in shower activity. S/SW winds this afternoon 5 to 10
knots could go variable at times, and will lessen in speeds
overnight. VFR will continue into Friday morning, with some
guidance suggesting a 20-40% chance of low cloud/fog development
across lower prone terminals.
KSEA...VFR conditions this afternoon. Scattered showers will
continue through the evening, could see brief MVFR conditions in
any shower that passes over the terminal. Additionally,
thunderstorm chances continue to remain low across the area
(15-20%), with low confidence in any impact to the terminal.
Southwesterly winds this afternoon 5 to 10 knots, will start to
turn more variable and light overnight. Will likely see a return
to southerly winds by Friday morning. MVFR patchy fog may
develop around the terminal early Fri morning (20-30%) for a
brief moment, but otherwise, VFR will continue.
Mazurkiewicz
&&
.MARINE...
No current advisories across the waters with winds and seas
continuing to gradually subside. Seas remain around 8 to 10 ft early
this afternoon over the coastal waters, but will gradually decay
through Friday. Broad low pressure remains in place, with showers
and a few thunderstorms remaining possible, which could bring
isolated gusty outflow winds. Otherwise, northerly winds develop
over the waters Saturday through the start of next week. A marginal
westerly push through the Strait of Juan de Fuca around Monday looks
to be the next potential period of advisory strength conditions.
Seas over the coastal waters subside further Saturday and remain in
the 3 to 5 ft range through the first half of next week.
&&
.SEW WATCHES/WARNINGS/ADVISORIES...
WA...None.
PZ...None.
&&
$$
NWS SEW Office Area Forecast Discussion