Brier Weather Station
Latitude N 47° 46' 49" Longitude W 122° 16' 48" Elevation 341 ft
829
FXUS66 KSEW 261614
AFDSEW
Area Forecast Discussion
National Weather Service Seattle WA
914 AM PDT Wed Aug 26 2026
.UPDATE...
Marine stratus is well entrenched across western Washington this
morning. With diurnal heating, stratus is slated to burn off
this afternoon to mostly clear skies. A slight chance of
thunderstorm is in the offing this afternoon as well, mainly
for the North Cascades. Any lingering wildfire smoke aloft will
push off and away into the evening. Highs today across the
interior will top out around the mid 70s to lower 80s. Coastal
sections are forecast to stay put in the 60s. The previous
discussion is below along with an updated aviation and fire
section.
&&
.SYNOPSIS...
Upper level trough offshore today moving inland Thursday. Trough
remaining over Western Washington through Saturday. Temporary
upper level ridge moving through Sunday. Another upper level
trough arriving the first part of next week.
&&
.SHORT TERM /TODAY THROUGH FRIDAY/...
Satellite imagery shows stratus along the coast, down the Strait
of Juan de Fuca to Whidbey Island and through the Lower Chehalis
Valley into the Southwest Interior east of I-5 at 3 am/10z.
Mostly clear skies over the remainder of the area. Temperatures
were in the mid 50s to lower 60s.
Upper level trough offshore with the trough axis still west of
130W this morning. Low level onshore flow will allow the stratus
to continue to fill in over the interior covering most of the
lowlands by 15z. The layer is less than 2000 feet thick. This
combined with the weakening onshore gradients will allow the
stratus to dissipate over the interior midday/early afternoon.
Stratus hanging tough all day along the coast. Much cooler today
with the marine push overnight. Highs in the 70s inland and mid
60s coast.
Upper level trough moving east tonight reaching Western
Washington Thursday. Chance of showers Thursday mainly coast and
mountains with a slight chance of a thunderstorm near the
Canadian border. Lows tonight in the 50s. Highs Thursday in the
mid 60s to mid 70s.
Upper level troughiness remaining over Western Washington
Thursday night into Friday with low level onshore flow. Chance
of showers continuing over the northern portion of the area.
Mostly cloudy and cool over the southern portion. Lows in the
50s. Highs Friday in the 60s and lower 70s. Felton
&&
.LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/...
Extended models in good agreement with upper level trough over
the area Saturday shifting east Saturday night. Temporary upper
level ridge moving through Sunday before another upper level
trough moves into the area for the first part of next week.
Showers likely north Saturday. Dry all areas Sunday with shower
chances returning Monday and Tuesday. Highs remaining cool, in
the 60s and lower 70s. Lows in the 50s. Current forecast high
for Seattle Tuesday is 69 degrees. This would end the
consecutive 70 degree plus days streak at 46 days, 8th longest
on record ( record 72 days June 29th to September 8th, 2017 ).
The last day Seattle had a high temperature below 70 degrees,
July 16th with 65 degrees.
Has it seemed like it hasn`t rained much in Seattle this year?
The yearly rain total is below normal but only by 9 percent
( 19.57 versus a normal of 21.55 inches ). What has happened
this year is that we have not had a lot of days with rain. So
far through the 25th, Seattle has recorded 71 days with
measurable rain this year. The record for the least number of
rain days between January and August is 72 days set in 1985
( 1985 the second driest year on record in Seattle with 25.13
inches ). Number two on the list of the least amount of rain
days between January and August is last year with 76 days. The
normal number of rain days between January and August is 97
days. Felton
&&
.AVIATION...
South to southwesterly flow aloft as upper level troughing
approaches western Washington. Marine stratus has expanded across
the lowlands, with an extensive mix of IFR/MVFR ceilings across most
western Washington terminals this morning. In some lower prone
areas, could see localized LIFR with the stratus. Stratus will
slowly erode by the early afternoon, with most inland terminals
seeing a rebound back to VFR by 19-20z. South to southwesterly winds
will continue throughout the day, increasing to 5 to 10 knots
throughout the afternoon.
KSEA...MVFR this morning in low stratus and light southwest winds.
Conditions will remain MVFR through 18z-19z, as stratus will begin
to erode with a return to VFR conditions by the early afternoon.
Winds will remain from the S/SW, and increase to 5 to 10 knots this
afternoon. Another round of low clouds will likely expand over the
terminal early Thursday morning.
Mazurkiewicz/15
&&
.MARINE...
A weak front will cross over the area waters today, with a
slight uptick in southerly winds over the coastal waters this
afternoon. Weak systems will continue to move over the coastal
waters through the end of the week, which will continue to
provide pushes down the Strait of Juan De Fuca, along with
increasing southerlies over the coastal waters. At this time,
winds look to remain under small craft advisory, although
headlines may be needed late in the week. Chances for isolated
thunderstorms over the waters increases on Thursday with the
passage of a frontal system, which may locally produce gusty
outflow winds and lightning.
Coastal seas will remain 4 to 6 feet through the weekend.
Mazurkiewicz
&&
.FIRE WEATHER...
Updated: Overall, the low level onshore flow producing good
overnight relative humidity recoveries and cooler daytime
temperatures will help ease fire weather concerns for the next few
days. However, models indicate increased thunderstorm probabilities
for the afternoon/evening for today and Thursday. There is a slight
chance ( 15-25 percent ) of isolated thunderstorms mainly in the
north Cascades but it can`t be ruled out around Mount Rainier. If
there is a thunderstorm it will not be accompanied by much rain and
it could produce erratic and gusty outflow winds impacting existing
fires. In addition, the lightning strikes pose a hazard and could
lead to new fire starts. JBB/Felton
&&
.SEW WATCHES/WARNINGS/ADVISORIES...
WA...None.
PZ...None.
&&
$$
NWS SEW Office Area Forecast Discussion