Brier Weather Station
Latitude N 47° 46' 49" Longitude W 122° 16' 48" Elevation 341 ft
748
FXUS66 KSEW 092025
AFDSEW
Area Forecast Discussion
National Weather Service Seattle WA
125 PM PDT Thu Jul 9 2026
.SYNOPSIS...A weak front will bring increasing clouds and cooler
temperatures across Western Washington Friday into Saturday.
Light rain chances also exist, particularly for portions of the
mountains. Upper ridging will build back into the Pacific
Northwest for warmer, dry conditions Sunday through Tuesday.
Onshore flow increases again during the middle of next week.
&&
.SHORT TERM /TONIGHT THROUGH SATURDAY NIGHT/...Mostly sunny
skies across the area today with weak high pressure aloft.
Temperatures will peak in the 70s for the majority of Puget
Sound this afternoon, with cooler temperatures along the coast
with continued onshore flow.
A weak front will move across Western Washington Friday through
Saturday leading to increased onshore flow. Mostly cloudy
conditions are expected on Friday, with a bit more in the way of
partial sunshine late Saturday. In addition, light rain
chances exist for the Cascades and Olympics, as well as from
King County northwards Friday morning into Saturday. Rainfall
amounts are expected to be light (if any), primarily less than
0.10". Temperatures will be a few degrees cooler both Friday
and Saturday.
&&
.LONG TERM /SUNDAY THROUGH THURSDAY/...A large scale upper level
ridge will build across much of the Interior Rockies and Central
US early next week. Western Washington will be located on the
northwest periphery of this ridge. This pattern will promote a
warming trend, with dry conditions, Sunday through at least
Tuesday. Minor HeatRisk is expected during this period, with a
10-35% chance of Moderate HeatRisk for Seattle metro southwards
to Olympia. Uncertainty grows in ensembles by Wednesday with at
least some indication of weak troughing developing offshore.
This would allow for an increase in onshore flow mid next week
with a slight cooling trend going into later next week. JD
&&
.AVIATION...Westerly to northwesterly flow aloft as a weak front
remains offshore. VFR conditions across all terminal sites this
afternoon. Onshore flow will continue tonight with a stronger
marine layer expected into Friday morning, with likely MVFR/IFR
ceilings at spots 05-09z spreading into the interior through the
morning hours. This layer looks to stick around for a bit before
dissipating around 20z-22z, rebounding back to VFR for Friday
afternoon. NW winds this afternoon 4 to 8 knots turning more
S/SW this evening through Friday morning.
KSEA...VFR conditions this afternoon will continue throughout
the evening. Latest guidance shows confidence in more widespread
MVFR ceilings early Friday morning 11z-16z as a marine layer
spreads through the interior. Northwesterly winds this
afternoon 4 to 8 knots will turn southerly and generally remain
the same speeds. VFR conditions return around 19-22z.
Mazurkiewicz
&&
.MARINE...Surface high pressure remains over the coastal and
offshore waters this afternoon. High pressure will weaken into
Friday as a weak surface low shifts southward toward to just
west of north Vancouver Island. An associated weak frontal
system will cross the waters Friday afternoon into Friday night
with little to no impact.
High pressure will rebuild Sunday into Monday. Diurnally driven
increases in westerlies can be expected in the Strait of Juan
de Fuca each the next several days.
Coastal seas remain 4 to 6 feet throughout much of the week.
Mazurkiewicz
&&
.FIRE WEATHER...The current onshore pattern will continue
through the weekend which will lead to continued excellent
nightly RH recoveries. Light drizzle or rain chances exist
Friday into Saturday, mainly for the Olympics and Cascades.
Rainfall amounts during this period would total less than 0.10".
A ridge of high pressure briefly rebuilds into the region Monday
and Tuesday. While the onshore pattern will largely remain in
place, warmer daytime temperatures and clear skies will likely
lead to RH values dipping into the 20-40% percent range, with
the lowest values in the south interior and Cascades Valleys.
This will allow fine fuels to continue to dry with elevated fire
weather conditions.
&&
.SEW WATCHES/WARNINGS/ADVISORIES...
WA...None.
PZ...Small Craft Advisory from 5 PM this afternoon to 2 AM PDT
Friday 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