Brier Weather Station
Latitude N 47° 46' 49" Longitude W 122° 16' 48" Elevation 341 ft
744
FXUS66 KSEW 261002
AFDSEW
Area Forecast Discussion
National Weather Service Seattle WA
302 AM PDT Wed Aug 26 2026
.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 will continue to
push onshore across the interior early this morning, with an
extensive mix of IFR/MVFR ceilings expected across much of the
area terminals this morning. In some lower prone areas, could
see localized LIFR with the stratus. Stratus will slowly erode
by early afternoon, with most terminals seeing a rebound back to
VFR by 18z. South to southwesterly winds will continue,
increasing to 5 to 10 knots throughout the afternoon.
KSEA...VFR conditions at the terminal this morning. MVFR stratus
will approach the terminal early this morning, generally around
12-14z. Conditions will remain MVFR through 17z-18z, 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.
Mazurkiewicz
&&
.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...
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. The exception
will be Thursday. There is a slight chance ( 15 percent ) of a
thunderstorm near the Canadian border. If there is a thunderstorm
it will not be accompanied by much rain and it could produce
erratic and gusty outflow winds in addition to the lightning
strikes. This could lead to new fire starts. Felton
&&
.SEW WATCHES/WARNINGS/ADVISORIES...
WA...None.
PZ...None.
&&
$$
NWS SEW Office Area Forecast Discussion