Brier Weather Station
Latitude N 47° 46' 49" Longitude W 122° 16' 48" Elevation 341 ft
029
FXUS66 KSEW 110324
AFDSEW
Area Forecast Discussion
National Weather Service Seattle WA
822 PM PDT Sat Oct 10 2026
.SYNOPSIS...
Slowly exiting low pressure will move southeastward tonight,
allowing showers to come to an end tonight. High pressure building
overhead brings drier conditions and near-normal temperatures into
early next week. Cooler and unsettled conditions may return mid-week
as series of systems move inland aimed at Vancouver Island. High
pressure will return by the end of the week, allowing for drier and
warmer conditions Thursday and Friday.
&&
.SHORT TERM /TONIGHT THROUGH MONDAY NIGHT/...
Current radar showing only a few blobs of precip left over W WA this
evening over central and eastern portions of King and Pierce
counties. Satellite shows clouds lingering over the east and south
Sound areas while western Whatcom and Skagit counties as well as
much of the coast seeing clear skies. Low level moisture may still
result in isolated patches of fog, especially in the more prone
areas of the SW interior. All that said, inherited forecast remains
on track and no evening updates are required. For further forecast
details, please refer to the Previous Discussion section below. 18
From Previous Discussion...A low pressure system will slowly meander
southeastward into Sunday, with wrap around moisture maintaining
light shower activity across the Pacific Northwest through the
evening. Most areas across western Washington will see high
temperatures shy of 60 degrees today. As the upper low moves
southeastward, dry northeast flow aloft filling in behind will bring
in cooler air with lows expected to dip into the mid 30s to mid 40s.
This will likely allow frost to form early Sunday morning for
portions of the southern Cascade foothills and valleys and areas
south of the Olympics, and a Frost Advisory remains in effect for
Sunday morning.
Weak ridging will build into British Columbia on Sunday with
continued dry northeast flow aloft over western Washington,
bringing slightly warmer daytime temperatures in the mid 50s to
lower 60s. Skies will be mostly clear Sunday into Sunday night,
with even cooler overnight temperatures generally in the 30s for
most areas. Frost will likely be more widespread early Monday
morning, and a Frost Advisory remains in effect for most areas
south of Seattle and along the Hood Canal and North Coast for
Monday morning.
The upper level ridge axis over British Columbia will shift
southward over the Pacific Northwest on Monday, bringing more
warming to the region. Highs will peak near normal under sunny
skies, reaching the upper 50s to mid 60s.
&&
.LONG TERM /TUESDAY THROUGH SATURDAY/...
Cloud cover will increase over western Washington on Tuesday as
a weak atmospheric river brings ample moisture to British
Columbia. While the majority of the precipitation is expected to
stay north, chances for rain increase on Tuesday along the
coast and over higher terrain. The decaying atmospheric river
system is set to shift southward late Tuesday into Wednesday,
bringing increasing chances for rain across western Washington.
However, the path of the atmospheric river remains fairly
uncertain at this time, with many ensemble members keeping
western Washington on the dry side.
A high pressure ridge will then build into the Pacific Northwest
on Thursday as another atmospheric river system traverses well
to the north. This will bring a few days of warming and drying,
with low level offshore flow and highs reaching the lower 70s by
Friday. Some uncertainty remains over how long the high pressure
will remain in place, with potential for troughing to break down
the ridge by the weekend and bring in some more rainfall and
cooler temperatures.
15
&&
.AVIATION...
VFR conditions favored this evening and tomorrow. Scattered showers
will subside this evening. Fog may form Sunday morning, with the
highest chances of seeing LIFR conditions in the southern interior
and mountain valleys. Northerly winds trending lighter overnight.
Breezy conditions expected again Sunday afternoon across Puget Sound
and northern interior with winds 8-12 kt and gusts 20-25 kt.
KSEA...VFR conditions tonight and tomorrow. Northerlies easing late
this evening to 2-5 kt. Northerly winds will increase again Sunday
afternoon to 8-11 kt and gusts to 20 kt. Fog may form near the
terminal, but not expected to bring direct impacts to the terminal.
29/41
&&
&&
.MARINE...
High pressure building over the interior of British Columbia will
lead to increasing northerly or offshore flow tonight into Sunday.
This will result in enhanced winds over the Northern Inland Waters
near the San Juan Islands, for which a Small Craft Advisory has been
issued. Additionally northerly winds will increase across Puget
Sound Sunday afternoon, with the 70-80% possibility for wind gusts
to exceed 21 kt. Winds will ease early next week as high pressure
over British Columbia weakens and broad surface ridging remaining
offshore. A weak frontal system will move across the waters late
Tuesday night into Wednesday.
Seas will hover around 6-9 feet this weekend, decreasing to 4-6 feet
early next week. Seas will briefly build on Wednesday but will
remain below 10 feet.
29/27/41
&&
.SEW WATCHES/WARNINGS/ADVISORIES...
WA...Frost Advisory from midnight tonight to 8 AM PDT Sunday for
Foothills and Valleys of Pierce and Southern King
Counties-Foothills and Valleys of Thurston and Lewis
Counties-Middle Chehalis River Valley.
Frost Advisory from midnight Sunday night to 8 AM PDT Monday
for Eastern Kitsap County-Foothills and Valleys of Pierce
and Southern King Counties-Foothills and Valleys of
Thurston and Lewis Counties-Foothills of the Western and
Southern Olympic Peninsula-Lake Crescent Area Including
US 101-Lowlands of Lewis and Southern Thurston Counties-
Lowlands of Pierce and Southern King Counties-Middle
Chehalis River Valley-Northern Hood Canal-Northern
Washington Coast-Olympia and Southern Puget Sound-
Southern Hood Canal-Willapa and Black Hills.
PZ...Small Craft Advisory until 5 AM PDT Sunday for Northern Inland
Waters Including The San Juan Islands.
&&
$$
NWS SEW Office Area Forecast Discussion