Renton, Virginia 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

676
FXUS66 KSEW 172346
AFDSEW

Area Forecast Discussion
National Weather Service Seattle WA
346 PM PST Wed Dec 17 2025

.SYNOPSIS...
A series of frontal systems will continue to produce unsettled
conditions across Western Washington into through early next
week with lowland rain, mountain snow, and breezy conditions at
times.

&&

.SHORT TERM /TONIGHT THROUGH FRIDAY NIGHT/...
Recent radar imagery depicts scattered showers across most of
the region, as post frontal showers continue from the
frontal system this morning. Light rain showers will continue
over the lowlands through this evening, along with snow showers
in the Cascades. High temperatures this afternoon have been in
the mid to upper 40s across the region, back to seasonal
normals. This lull in activity will be brief as another system
moves across western Washington late tonight into Thursday
morning. The bulk of this precipitation with this system will
be aimed towards northwest Oregon, but it will still generally
be another wet day across the area, with rain totals across the
lowlands generally around 0.25-0.75 inches, with locally higher
amounts more in the south sound. For information regarding river
flooding, see .HYDROLOGY down below for more details.

Locally windy conditions can be expected across along the
coast, especially Whidbey Island northward through Bellingham,
and generally south of the Sound with increasing S/SW winds.
Snow levels generally 2500 to 3000 feet this afternoon will
hover this evening and into the overnight hours.. with snow
accumulations around 5 to 10 inches expected over the Cascades.
Additionally, as this system moves over the region, warmer air
aloft will increase snow levels to 6000 to 7000 feet by late
Thursday morning into the afternoon, which leaves a brief time
window where freezing rain could be possible. Uncertainty exists
in how long the warm air lingers, as snow levels immediately
drop down to 1500 to 2000 feet by late Thursday evening,
transitioning the rain mix to snow.

We will see snow levels remain at 1500 to 2000 feet through
Friday and into the weekend where we could see significant
continuous snowfall in the mountains, a good thing if you like
to ski or snowboard.

&&

.LONG TERM /SATURDAY THROUGH WEDNESDAY/...
The unsettled weather pattern will continue into the early half
of next week, where we will continue to see lowland rain,
mountain snow, and at times, breezy conditions across western
Washington. Temperatures look to settle right around seasonal
normals during this period, in the mid to upper 40s across most
of the region.

&&

.AVIATION...
Satellite this afternoon is showing some clearing in the cloud
coverage this afternoon in the central terminals. All terminals are
reporting VFR except in the Cascades, where a few lower CIGs and VIS
remain with continuing showers/snow showers. Precipitation returns
with a frontal system passing through tonight/tomorrow with showers
returning later tonight and continuing into Thursday. Rain rates are
expected to be on the lighter side, so visibility impacts are not
expected to be as severe as the previous systems (lower visibilities
will continue in the mountains). As the showers continue, ceilings
will lower Thursday morning. The highest likelihood is MVFR, with an
elevated risk of IFR for terminals around the Olympics (including
the coast and the Kitsap (from 18Z-00Z Thursday/Friday). Ceiling
improvements to VFR are expected late Friday afternoon for most
terminals. Winds at the surface remain out of the southwest 8-12 kt
(with gusts likely linger at 25 kt in the Puget Sound through the
evening). Models have winds increasing tonight/Thursday along the
coast and interior, with winds 15-20 kt gusting to 30-35 kt likely
through the day.

KSEA...VFR continues this afternoon with ceilings decreasing to MVFR
this evening after 06Z. There is a small chance (20-25%) of IFR
between 18Z-22Z Thursday. SW winds 8-12 kt gusting to 25 kt will
likely continue through the evening. Another round of breezy winds
expected Thursday afternoon with sustained speeds of 10-20 kt and
gusts greater than 35 kt possible (60-80%) after 21Z. Ceilings will
improve to VFR late Thursday evening.

HPR

&&

.MARINE...
Weak high pressure will weaken tonight with another frontal system
expected to move over area waters on Thursday. This system will
bring elevated winds and seas, for which various headlines have been
issued. The strongest winds will be along the coastal waters and
East Strait with gusts up to 40-45 kt likely, for which a Gale
Warning is set to go into effect early Thursday morning. Held off on
upgrading the Small Craft Advisory to a Gale Warning for the Western
Strait on Thursday, due to low confidence (30-40% chance) of
exceeding 34 kt gusts. However, cannot rule out an occasional low-
end gale gust at times. Seas will decrease slightly tonight to 10-13
ft and then build to 11-15 ft by late Thursday morning. Additional
systems are expected to move over area waters this weekend and into
early next week.

&&

.HYDROLOGY...Precipitation will continue at times through tonight,
before another weather system bring additional, steadier
precipitation on Thursday. Snow levels will remain lower into
Thursday morning, around 2500 to 3000 feet, before briefly rising to
5000 to 7000 feet Thursday afternoon. Snow levels will then fall to
1500 feet on Friday. QPF amounts through Friday morning will range 2
to 3 inches for the majority of the Olympics and Cascades, with
localized higher amounts over the Cascades of Pierce and Lewis
Counties.

Ongoing river flooding continues for numerous rivers off the
Cascades, as well as the Skokomish River in Mason County. Rivers
will continue to remain elevated due to the continued precipitation.

A Flood Watch also remains in effect for Skagit, King, Pierce,
Thurston, and Grays Harbor Counties through Friday afternoon due to
the next system on Thursday and rivers currently running high. The
Flood Watch has been cancelled for Lewis, Snohomish, and Whatcom
Counties as no further flooding is expected with the additional
precipitation from the next weather system.

The landslide threat will remain high through at least Friday.
JD

&&

.SEW WATCHES/WARNINGS/ADVISORIES...
WA...Coastal Flood Advisory from 7 PM this evening to 1 AM PST
     Thursday for San Juan County.

     Flood Watch through Thursday afternoon 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-City of Seattle-Downtown
     Everett / Marysville Area-Eastside-Foothills and Valleys
     of Central King County-Foothills and Valleys of Pierce
     and Southern King Counties-Foothills and Valleys of
     Snohomish and Northern King Counties-Foothills and
     Valleys of Thurston and Lewis Counties-Foothills and
     Valleys of the North Cascades-Foothills of the Western
     and Southern Olympic Peninsula-Grays Harbor County Coast-
     Lower Chehalis River Valley-Lowlands of Lewis and
     Southern Thurston Counties-Lowlands of Pierce and
     Southern King Counties-Lowlands of Western Skagit and
     Northwestern Snohomish Counties-Lowlands of Western
     Whatcom County-Middle Chehalis River Valley-Olympia and
     Southern Puget Sound-Olympics-Shoreline / Lynnwood /
     South Everett Area-Willapa and Black Hills.

     Winter Weather Advisory until 10 AM PST Thursday 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 6 PM PST Thursday 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-Grays Harbor Bar-
     West Entrance U.S. Waters Strait Of Juan De Fuca.

     Gale Warning until 6 PM PST 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 4 PM PST this afternoon for
     Northern Inland Waters Including The San Juan Islands.

&&

$$