Brier Weather Station
Latitude N 47° 46' 49" Longitude W 122° 16' 48" Elevation 341 ft
325
FXUS66 KSEW 092154
AFDSEW
Area Forecast Discussion
National Weather Service Seattle WA
254 PM PDT Tue Jun 9 2026
.SYNOPSIS...
Showers will taper off outside of convergence zone showers and
thunderstorms today, with drier and warmer conditions settling
into the region through the weekend and into early next week.
Areas of Moderate (Orange) HeatRisk will expand across the
lowlands by Sunday and continue into Monday with pockets of
Major (Red) HeatRisk possible.
&&
.SHORT TERM /TODAY THROUGH THURSDAY NIGHT/...
A frontal system moved across the region earlier today, leaving
widespread breezy winds and light shower activity in its wake. A
Puget Sound Convergence Zone is well underway this afternoon
over Snohomish County, and has produced a few lightning strikes
so far in heavier shower activity. While most other areas dry
out, convergence zone activity is expected to persist overnight
and will likely be stalled over Snohomish County due to breezy
southwesterly winds.
Wednesday will kick off a warming and drying trend across
western Washington as weak high pressure passes over the region
and a high pressure ridge begins to build offshore. Wednesday
morning will likely feature another round of marine stratus
creeping inland, with sunny skies prevailing by the afternoon.
The region will see some warming, though temperatures will still
peak a few degrees below normal on Wednesday in the mid to upper
60s across the lowlands.
Northwesterly flow aloft will prevail on Thursday as the upper
level ridge offshore to the south slowly amplifies northward.
Despite a cool and cloudy morning, Thursday will bring
additional warming with sunny skies in the afternoon. Highs will
peak in the upper 60s to lower 70s. This will introduce
widespread Minor (Yellow) HeatRisk across much of the lowlands.
&&
.LONG TERM /FRIDAY THROUGH MONDAY/...
A warming and drying trend will continue into the weekend as an
upper level ridge continues to build offshore. A thermal trough
moving up the coastline will reach western Washington by late
Saturday, with easterly offshore flow developing as a result on
Sunday and Monday. Temperatures Sunday are on track to peak in
the upper 80s to lower 90s, with even warmer conditions south
and east of the Puget Sound Monday with temperatures peaking in
the low to mid 90s. This will introduce widespread Moderate
(Orange) HeatRisk both days, with up to a 30% to 50% chance for
Major (Red) HeatRisk near the metro areas on Monday. A few
locations may even break daily temperature records on Sunday and
Monday. Longer range models suggest a pattern change may be on
track for the middle of next week, bringing an end to the
incoming heat wave.
15
&&
.AVIATION...
A post-frontal convergence zone continues in Snohomish County this
afternoon. There remains a 20% chance of thunder with this activity
through this evening. Conditions with this convergence zone have
dropped locally to MVFR/IFR at times, with cloud tops less than
20,000 ft. Showers in the southwest interior/coast have also
resulted in brief drops to MVFR as they pass over the terminal. The
shower activity will continue into early Wednesday morning. Breezy
southwest winds also continue this afternoon, with sustained winds
up to 20 kt and gusts up to 30 kt. Winds will taper down tonight
into Wednesday to around 4-8 kt, with only the Strait of Juan de
Fuca area remaining breezy part way into Wednesday. A few Puget
Sound locations will see winds turn to the north late Wednesday
afternoon (via diffluence from the strait). There remains a 40-60%
of widespread MVFR ceilings redeveloping tonight/Wednesday morning
through 18-21Z (highest chance for LIFR/IFR conditions remain in the
mountains).
KSEA...VFR through tonight, with convergence zone activity remaining
north of the field. Will remain breezy through tonight with
sustained winds 15-20 kt with gusts up to 30 kt diminishing to
around 4-8 kt Wednesday. Potential for north winds at around 5 kt or
less after 00Z Thursday. MVFR probabilities increase to 40-60%
around 10Z through 20Z, before scattering out.
HPR
&&
.MARINE...
A strong onshore push in wake of a front that went through late last
night/this morning continues. Showers will continue across a
majority of the waters through the evening/Wednesday morning. The
only threat for thunder remains in the north Puget Sound/water areas
adjacent to Whidbey Island with a convergence zone continuing into
the evening. Winds remain breezy across the interior waters, with
Strait of Juan de Fuca winds continuing to remain the breeziest with
gale gusts through this evening into tonight. Breezy southwest winds
also continue in the Puget Sound, Admiralty Inlet, and Northern
Inland Waters through tonight. Diurnal pushes through the Strait of
Juan de Fuca will continue through the week, although probability
has decreased with the potential for small craft winds. A thermal
trough building along the coast this weekend/early next week may
result in periods of offshore flow.
Seas at 6-8 ft today into Wednesday will decrease to 4-6 ft Thursday
through the weekend/next week, with a brief increase to 6-8 ft seas
Friday.
HPR
&&
.FIRE WEATHER...
After some wetting rains, western Washington will see a warming
and drying trend settle into the region through early next week.
A thermal trough will develop offshore by late Saturday, causing
winds to shift easterly offshore. This will allow fine fuels to
cure, with RH dropping to near critical levels over the weekend.
Larger fuels may also see drying with this heat wave. Fire
weather concerns will remain elevated into the weekend and will
peak on Monday, corresponding with the warmest expected day of
the heat wave. The thermal trough will shift inland on Monday
before potentially shifting eastward by Tuesday and allowing the
region to see cooler temperatures.
15
&&
.SEW WATCHES/WARNINGS/ADVISORIES...
WA...None.
PZ...Small Craft Advisory until 2 PM PDT this afternoon for West
Entrance U.S. Waters Strait Of Juan De Fuca.
Gale Warning until 5 AM PDT Wednesday for Central U.S. Waters
Strait Of Juan De Fuca-East Entrance U.S. Waters Strait
Of Juan De Fuca.
Small Craft Advisory until 11 PM PDT this evening for
Admiralty Inlet-Northern Inland Waters Including The San
Juan Islands.
Small Craft Advisory until 8 PM PDT this evening for Puget
Sound and Hood Canal.
&&
$$
NWS SEW Office Area Forecast Discussion