Brier Weather Station
Latitude N 47° 46' 49" Longitude W 122° 16' 48" Elevation 341 ft
106
FXUS66 KSEW 091547
AFDSEW
Area Forecast Discussion
National Weather Service Seattle WA
847 AM PDT Tue Jun 9 2026
.SYNOPSIS...
Front moving east of the Cascades this morning. Trailing upper
level trough moving over the area later today. The trough will
move east Wednesday. Upper level ridge beginning to build
Wednesday night. Weak system moving by to the north will slow
the ridge building Thursday. Strong upper level ridge building
offshore Friday with the ridge moving east through the weekend.
Low level flow going offshore Saturday night with record highs
possible Sunday and Monday.
&&
.SHORT TERM /TODAY THROUGH THURSDAY/...
The latest forecast generally remains on track, with updates to
the aviation section below. Front moving east early this
morning with trailing upper level trough moving over the area
later in the day. Strong westerly push down the Strait of Juan
de Fuca behind the front with a convergence zone forming over
Snohomish and Southern Skagit county. Breezy southwesterly winds
behind the front coming up the Puget Sound will keep the
convergence zone north of the King county line. Shower coverage
increasing and a slight chance of thunderstorms this afternoon
with the trough overhead. It will be another cool day with highs
in the mid 50s to lower 60s.
Upper level trough hanging over the area tonight keeping at
least a chance showers in the forecast. Southerly surface
gradients weaken overnight allowing the convergence zone to
drift south into King county after midnight. Lows in the mid 40s
to lower 50s.
Trough moving east Wednesday bringing an end to the shower
threat. Convergence zone dissipating in the Central Cascades
early. Onshore gradients weakening during the day. This combined
with the near solstice sun will dissipate the marine layer in
the afternoon giving the area some sunshine. High temperatures
will be warmer but still a little below normal, in the 60s.
Upper level ridge starts to build Wednesday night but a weak
system riding by well to the north Thursday puts a temporary
halt to the ridge building. Even so temperatures aloft warming
and low level flow remains flat. With plenty of sunshine highs
Thursday getting into the mid 60s to mid 70s. Lows Thursday
morning will be a little cool, in the 40s. Felton
&&
.LONG TERM /THURSDAY NIGHT THROUGH MONDAY/...
Upper level ridge building offshore Thursday night with the
ridge axis near 140W through Friday. Ridge shifting east over
the weekend with 500 mb heights going from the mid 570 dms to
the upper 580s and lower 590 dms by Sunday afternoon. Thermally
induced surface trough moving up the coastline reaching
Washington Saturday night with the low level flow going offshore
Sunday and Monday. Temperatures aloft warming with the ridge
building. 850 mb temperatures peaking around plus 20C Monday.
All this adds up to a warming trend through the period with
possible record highs Sunday and Monday. Highs in the 70s
Friday warming to the upper 70s to mid 80s Saturday, 80s Sunday
and 80s to mid 90s Monday. Lows in the mid 40s to lower 50s
Thursday night warming to the 50s and lower 60s by Sunday night.
Minor HeatRisk Friday and Saturday increasing to moderate
Sunday and Monday. Right now Monday looks to be the peak of the
heat.
Here is a list of some record highs for Sunday and Monday.
Seattle Sunday 86 degrees set in 1988 and Monday 88 set in 1963.
Olympia 88 degrees both days, 1999 for Sunday and 1963 for
Monday. Bellingham 83 in 1988 Sunday and 82 in 1961 Monday.
Hoquiam 79 in 1988 Sunday and 81 in 1961 Monday. Quillayute 84
in 1988 Sunday and 80 in 1969 Monday.
Felton
&&
.AVIATION...
A cold front has moved through the terminals this morning under a
trough, with flow increasing out of the northwest today behind the
trough. Lingering showers will continue through today, with an
organized convergence zone continuing in Snohomish County through
most of the day today. Local IFR conditions will likely continue at
times in the convergence zone with reduced visibilities/ceilings
from the steady rain. Outside of the zone, ceilings have improved to
MVFR and VFR for most terminals, with ceilings trending to VFR
through the afternoon for thew interior. MVFR likely lingers along
the coast, and lower ceilings in the mountains. There is a 40-60%
chance of MVFR ceilings redeveloping Wednesday morning, with
ceilings as low as 1,000 ft. Breezy southwest winds have picked up
in Puget Sound this morning, with gusts up to 25 kt through
Wednesday morning. Gusty west winds in the Strait of Juan de Fuca
will linger into Wednesday, with highest winds today up to 30-35 kt.
Coast will see winds turn to the northwest through today, with gusts
up to 20 kt.
KSEA...Ceilings have improved to MVFR, ensembles keep the likelihood
of MVFR through roughly 20-23Z, with improvement to VFR later in the
afternoon/evening. Breezy winds out of the southwest will pick up
through the day, with sustained winds 10-15 kt gusting to 25 kt
through the day. Few vicinity showers will linger around the
terminal (a more organized convergence zone will persist to the
north of the terminal). There is a 40-60% chance of MVFR
redeveloping overnight/Wednesday morning (due to lingering moisture).
HPR
&&
.MARINE...
Northwesterly winds over the coastal waters expected to
maintain SCA winds and seas throughout the remainder of the morning
before easing by noon today and becoming more westerly. Southwest
winds also increase for interior waters this morning and continuing
through the afternoon. Small Craft Advisory winds and gusts are
expected for most waters with this strengthening onshore flow. A
strong west push through the Strait of Juan de Fuca is expected to
result in gale force wind gusts for the central and eastern Strait
and inherited Gale Warning looks good. Winds slowly ease tonight
into Wednesday.
Winds become lighter Wednesday as high pressure builds back into the
Coastal Waters. Northwest winds over the Coastal Waters increase
Thursday into late week as high pressure continues to build
offshore. Flow will transition to offshore at times over the weekend
into early next week as a thermal trough expands northwards along
the coast.
Seas will range between 6 to 9 feet today with isolated areas in the
central and southern outer coastal waters seeing 10 or 11 foot seas.
Not expected to be widespread before seas begin to ease this
afternoon, inherited 11 AM expiration for the current SCA looks to
cover this aspect of the forecast well. Seas subside to 4 to 7 feet
by Wednesday and remain in this range into late week.
18/JD
&&
.FIRE WEATHER...
No fire weather concerns until the warm temperatures beginning
this weekend. Low level offshore flow will drive minimum
relative humidity values down below 30 percent Sunday and
Monday. Some the drier locations like Cascade valleys and the
Southwest Interior minimum RH values will drop into the teens.
Fine fuels will be approaching critical thresholds this weekend
and larger fuels will be drying out as well. Elevated fire
weather conditions beginning Saturday and continuing through the
early part of next week across the area.
Felton
&&
.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 11 PM PDT this evening 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.
Small Craft Advisory until 11 AM PDT this morning for Coastal
Waters From Cape Flattery To James Island 10 To 60 Nm-
Coastal Waters From Cape Flattery To James Island Out 10
Nm-Coastal Waters From James Island To Point Grenville 10
To 60 Nm-Coastal Waters From James Island To Point
Grenville Out 10 Nm-Coastal Waters From Point Grenville
To Cape Shoalwater 10 To 60 Nm-Coastal Waters From Point
Grenville To Cape Shoalwater Out 10 Nm.
&&
$$
NWS SEW Office Area Forecast Discussion