Brier Weather Station
Latitude N 47° 46' 49" Longitude W 122° 16' 48" Elevation 341 ft
716
FXUS66 KSEW 230345
AFDSEW
Area Forecast Discussion
National Weather Service Seattle WA
744 PM PST Sun Feb 22 2026
.SYNOPSIS...
An upper-low will continue to spin offshore as the pattern
remains active into the new week. Recurring spells of lowland
rain and mountain snow is favored. Temperatures will tread
slightly below to near average throughout the next several days.
&&
.SHORT TERM /TONIGHT THROUGH TUESDAY NIGHT/...
Latest radar shows rain associated with an incoming AR event over at
least the southern two-thirds of the CWA with rainfall generally
ranging light to some moderate spots, especially over portions of
Grays Harbor and Mason counties at the time of this writing. As
precip continues to spread northeasterly over the area, should see
widespread lowland rain and mountain snow persist overnight and into
Monday. Inherited forecast and headlines look good with no evening
update needed.
For additional forecast details, please refer to the Previous
Discussion section below. 18
From Previous Discussion...Broad troughing remains fixed across the
NE PAC with ridging over the Intermountain West. In the Northwest,
the aforementioned broad trough/upper-low complex continues to
barrel an occluded 980mb frontal system into the region. This
feature has lead to breezy winds, lowland rain and mountain snow.
Low- topped thunderstorms have also been observed this afternoon as
low to mid-level lapse rates range anywhere between 7 to 7.5 c/km.
This environment along with meager CAPE has done just enough leading
to lightning strikes over the coastal waters and WA coast.
For tonight, moisture associated with a weak to moderate AR will
funnel into the region - increasing the coverage of widespread
lowland rain and lifting snow levels up to 3,000 to 4,000 ft.
Cross-Cascade gradients remain negative and with steadier
precipitation rates in concert with offshore flow, snow should
become the dominant precipitation type overnight as hi-res
models reflect evaporative cooling very well. A Winter Weather
Advisory has been expanded and now includes Snoqualmie and White
Pass. Overnight lows are to bottom into the lower 40s.
Mountain snow and lowland rain will gradually progress off and
away on Monday as steadier rain transitions to showers by the
afternoon- evening. 24-hour rainfall totals ending Monday
evening range between 0.50 to 1.00" of QPF for much of the
lowlands. Lowlands north of Everett will see 0.25 to 0.50". NBM
has a 30-40% chance of rainfall exceeding an inch Olympia south.
The bulk of the moisture will remain over Oregon and eastward
on Tuesday as a transient ridge replaces it. Can`t rule out
straggling showers during the day - mainly over the mountains
with aid of orographics but it`ll be the drier day here in the
short-term forecast. High temperatures will top out in the mid
to upper 40s with overnight lows in the mid to upper 30s.
&&
.LONG TERM /WEDNESDAY THROUGH SUNDAY/...
Models have the upper-low center becoming closed off from the
mean flow in the long-term. Guidance suggests a rex block
forming over the NE PAC as a high center noses into the Bering
Sea while sitting on the northern periphery of the upper-low.
This set-up puts us under a regime of northwesterly flow aloft
through Sunday with embedded systems, maintaining the chance of
PoPs daily. No threat for heavy precipitation is on horizon
according to the latest ECMWF/GFS ensemble runs but we`ll keep a
look out. The NBM suggests temperatures will be near average
through the long-term forecast.
McMillian
&&
.AVIATION...
A broad upper level trough will remain offshore into Monday
producing west to southwest flow aloft over Western Washington. Rain
will increase across the area overnight ahead of another frontal
system with ceilings gradually deteriorating to MVFR thresholds most
terminals. MVFR and a few pockets of IFR in rain at times will
continue into midday Monday before lifting toward late afternoon or
early evening as a frontal boundary shifts east of the area.
KSEA...Rain will increase overnight as a slow moving frontal system
approaches the area. Ceilings are expected to lower to 1500 to 2500
feet toward early morning. The front will shift east of the area
after 21Z with ceilings improving to low end VFR by late afternoon
or early evening. Surface winds southeasterly 7 to 10 knots becoming
southerly 10 to 15 knots before daybreak then easing in the
afternoon. Winds will then veer to N/NE Monday evening/night.
27
&&
.MARINE...
Winds across the outer waters will continue to gradually ease and
shift more southwesterly today as a frontal system stemming from a
deep low pressure system well offshore continues to move inland.
Small Craft winds will hold on a little longer across the inland
waters, with southerly winds tapering off overnight. Seas will also
continue a lowering trend today as a large southerly swell moves out
of the area, with seas easing to about 8 to 12 feet overnight
tonight. Seas are expected to decrease to below 10 feet by Monday
afternoon alongside easing winds offshore.
A weaker frontal system will then move across the area waters on
Monday and will be followed by high pressure building back over the
coastal waters in its wake. Another frontal system will cross area
waters on Wednesday, with potential for westerly winds through the
Strait of Juan de Fuca to reach gale force on Wednesday and
Thursday. Gusts over the coastal waters may also reach Small Craft
levels on Wednesday and Thursday.
Seas will gradually subside towards 6 to 8 feet through the day on
Monday and further ease towards 5 to 7 feet by Tuesday. Waves will
build to around 8 to 10 feet over the outer coastal waters by
Thursday, with another round of seas reaching 9 to 12 feet over the
coastal waters by the end of the week.
15
&&
.HYDROLOGY...
No river flooding is expected over the next 7 days.
&&
.SEW WATCHES/WARNINGS/ADVISORIES...
WA...Wind Advisory until 2 PM PST this afternoon for San Juan
County.
Winter Weather Advisory from 8 PM this evening to 1 PM PST
Monday for Cascades of Pierce and Lewis Counties-Cascades
of Snohomish and Northern King Counties-Cascades of
Southern King County-Cascades of Whatcom and Skagit
Counties.
PZ...Small Craft Advisory until 10 PM PST this evening for Grays
Harbor Bar-Puget Sound and Hood Canal.
Gale Warning until 4 PM PST this afternoon for Central U.S.
Waters Strait Of Juan De Fuca-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-East Entrance U.S. Waters Strait Of
Juan De Fuca-West Entrance U.S. Waters Strait Of Juan De
Fuca.
Small Craft Advisory from 4 PM this afternoon to 4 AM PST
Monday for East Entrance U.S. Waters Strait Of Juan De
Fuca.
Small Craft Advisory until 4 AM PST Monday for Admiralty Inlet-
Northern Inland Waters Including The San Juan Islands.
Small Craft Advisory from 4 PM this afternoon to 4 PM PST
Monday 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