Brier Weather Station
Latitude N 47° 46' 49" Longitude W 122° 16' 48" Elevation 341 ft
137
FXUS66 KSEW 291717
AFDSEW
Area Forecast Discussion
National Weather Service Seattle WA
1017 AM PDT Fri May 29 2026
.SYNOPSIS...
Upper level low well south of the area will make its way into
the Plains Saturday while an upper level trough remains
offshore. Onshore flow in the lower levels. The trough will
move inland Saturday night. Upper level ridge building over
Western Washington Sunday will remain over the area through
Tuesday. A weakening front will move through Wednesday.
&&
.SHORT TERM /TODAY THROUGH SUNDAY/...
No major changes to the short/long term sections this morning.
-HPR
Middle and high level clouds associated with the convection
have spread over parts of Western Washington. In the lower
levels a marine push in progress with stratus already into the
Central Puget Sound at 3 am/10z. Doppler radar has convergence
zone showers over Snohomish and King county. Temperatures were
in the 50s.
Little change in the pattern the next couple of days with an
upper level trough offshore and varying degrees of low level
onshore flow. Convergence zone moving very little this morning
before dissipating this afternoon. Middle level clouds moving
out of the area later today but with the onshore flow remaining
intact skies will be at least mostly cloudy this afternoon after
a cloudy morning. Little change in the temperature today with
highs near 60.
Another surge of westerlies through the Strait of Juan de Fuca
tonight could re-energize the convergence zone over the Central
Puget Sound. Mostly cloudy to cloudy skies outside the
convergence zone. Lows tonight in the 40s.
Marine layer over the area Saturday will retreat back to the
coastline in the afternoon as low level onshore flow begins to
weaken. Temperatures slightly warmer with highs in the upper 50s
to mid 60s.
Weak upper level trough offshore moving inland Saturday night
will have little in the way of moisture associated with it.
Onshore gradients continuing to weaken Saturday night and by
Sunday the low level flow goes light. Upper level ridge
beginning to build over the area Sunday. This along with the
weakening onshore flow will minimize the marine layer Saturday
night into Sunday morning resulting in a sunny day Sunday. Highs
getting back to near normal, 60s and lower 70s. A little on the
cool side Sunday morning with the colder locations getting into
the upper 30s. Lows elsewhere in the 40s.
Seattle-Tacoma airport has recorded 0.02 inches of rain this
morning. This is the 63rd day with measurable rain so far this
year. If there is no more rain days this month this will tie for
the 5th lowest number of rain days in the first five months of
the year since records started at the airport in 1945. Have to
go back to 1985 to find a year with a lower number of rain
days ( 56 days ) in January through May. The normal number of
rain days for January through May in Seattle is 78 days, record
low 54 days in 1949, record high 98 days in 1961. Felton
&&
.LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/...
Extended models in good agreement with the upper level ridge
remaining over Western Washington through Tuesday. Low level
flow turning offshore Monday night into Tuesday making Tuesday
possibly the warmest day of the year. The heat is short lived.
Surface ridge out ahead of the next weather system moving into
the coastal waters Tuesday night. Rapidly increasing onshore
flow and the resulting marine push will bring clouds and cooler
temperatures back to the area. What is left of the front moving
through Wednesday. Zonal flow aloft with low level onshore flow
Thursday.
Highs Monday in the 70s and lower 80s warming to the 80s and
lower 90s Tuesday. Moderate HeatRisk Tuesday. Highs cooling into
the 60s and lower 70s Wednesday with mid 60s to mid 70s
Thursday. Lows in the 40s Sunday night, mid 40s to mid 50s
Monday night through Wednesday night. Not expecting any records
to be broken Tuesday.
&&
.AVIATION...
Southwest flow aloft will develop today with a broad upper
level trough over the Gulf of Alaska. Onshore flow continues in
the low levels. Showers continue across the area, with convergence
showers across the Sound and a band of showers currently moving
east of the Sound. Current conditions at the area terminals are
a mix of IFR to MVFR across the interior in shower activity and
VFR outside of the shower activity. A gradual lifting of ceilings
is expected this afternoon, but areas of MVFR may linger around
any remaining convergence zone activity. Most areas should
improve to VFR by early evening.
KSEA...MVFR ceilings with scattered showers are expected to
continue into the terminal through midday. Ceilings are then
expected to gradually lift with shower activity diminishing. VFR
is expected after around 22Z. Surface winds S/SW 7-12 knots
this morning will become NE at 8-12 kt by this afternoon, around
22Z.
27/14
&&
.MARINE...
Strong onshore flow will persist today with gales expected along
the Strait of Juan de Fuca. Winds will remain between 15-25 kt
across the coastal waters before easing late tonight. Seas will
hover between 10-16 ft throughout the day, before subsiding to
7-9 ft late tonight into Saturday. Onshore flow will ease over
the weekend allowing for winds and seas to continue to ease and
subside. Weak offshore flow will develop early next week with a
thermal trough forming near the coast.
27/14
&&
.HYDROLOGY...
The daily hydrology discussion has ended until the start of the
next rainy season; it will only be updated during this time as
needed.
&&
.SEW WATCHES/WARNINGS/ADVISORIES...
WA...None.
PZ...Small Craft Advisory until 11 PM PDT this evening for
Admiralty Inlet-Grays Harbor Bar-Northern Inland Waters
Including The San Juan Islands.
Small Craft Advisory until 3 AM PDT Saturday 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 5 AM PDT Saturday 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