Renton, Virginia 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

330
FXUS66 KSEW 220427
AFDSEW

Area Forecast Discussion
National Weather Service Seattle WA
827 PM PST Sat Dec 21 2024

.SYNOPSIS...The active pattern continues with multiple frontal
systems moving through the area bringing periods of rain, mountain
snow, and gusty winds. The focus shifts towards Christmas into
late next week with potentially higher-impact systems with heavy
rain and snow and gusty winds, especially when combined with
holiday travel.

&&

.SHORT TERM /TODAY THROUGH MONDAY/...Rinse. Lather. Repeat.
Western Washington is once again between weather systems this
evening with a few residual showers crossing the region. The next in
a series of systems will come ashore tomorrow with rain reaching the
coast around dawn and spreading into the interior by midday. This
will bring another round of gusty winds to coastal areas...though
guidance suggests that they`ll be marginally weaker than that of
this morning. Shortwave ridging brings another short-lived drying
trend on Monday before, you guessed it, another system brings the
next round of rain and mountain snow Monday night into Tuesday. All
of this is leading toward what is expected to be a particularly
wet/windy period surrounding Christmas Day and Boxing Day with
increasing impacts from heavy rain, wind, and mountain snow. Best to
stay tuned to the forecast if you`ve got travel plans later in the
upcoming week. Current forecasts are on track. Previous discussion
follows with minor update to hydrology section for near term minor
flooding on the Skokomish.  27

Light rain continues to work its way through Western Washington this
afternoon as an occluded front moves through the area. Breezy south
to southeast winds accompany this frontal passage, with the
strongest winds being observed along the coast, where a wind
advisory remains in effect until 2 PM this afternoon. Temperatures
today hover a few degrees on either side of 50. A few isolated
showers and perhaps a lightning strike or two will follow behind the
front late this afternoon into tonight. A brief break in the rain is
expected overnight tonight before the next frontal system arrives
tomorrow morning. Tomorrow looks to be almost a repeat of today,
with another round of mostly light rain for the lowlands (more
significant rainfall in the mountains) and breezy southeasterly
winds--strongest along the coast and through the north interior.
There appears to be a bit better chance for a few isolated
thunderstorms Sunday afternoon, but the best chances remain
confined to the Pacific coast. Snow levels will hang around 3500
to 4000 ft this weekend, with light snow accumulation expected at
Stevens and White Pass, but mostly rain at Snoqualmie Pass.

Another brief dry period is expected through most of the day on
Monday before another frontal system moves through Monday night
into Tuesday. The low pressure center will be relatively closer
to the region (near the northwest tip of Vancouver Island), and
with that, gusty east to southeast winds are more probable through
the gaps in the Cascades and through the Strait of Juan de Fuca
overnight Monday into Tuesday. QPF with this system will again be
mostly focused in the mountains with light amounts forecast for
the lowlands. Snow levels look to be higher with this system with
warmer temperatures in the forecast, through east wind may carry
below-freezing air to the tops of the passes and create a wintry
mix.

.LONG TERM /TUESDAY THROUGH FRIDAY/...Showers linger into Tuesday
as the front quickly moves through the area in the morning. Focus
then shifts onto Christmas and the end of next week as additional
systems bring a setup closer to an atmospheric river keeping
precipitation and gusty winds in the forecast. QPF looks to be
more hydrologically significant, and snow levels around 3000 ft
over the Cascades may bring rounds of heavy snow to all the
Cascade passes starting Christmas day.

62

&&

.AVIATION...Post-frontal showers under S/SW flow this evening with
showers diminishing after midnight. Ceilings mainly VFR. Gusty S
winds to 20-25 kt through 06Z. Rain spreading inland again on Sunday
morning with possible MVFR conditions.

KSEA...Showers in the vicinity through this evening with SW winds 8-
12 kt. Rain spreading in by 18z Sunday with possible MVFR
conditions. 33

&&

.MARINE...The next in a series of strong frontal systems will
cross western WA on Sunday for another round of elevated wind and
seas. Gales are forecast over the Coastal Waters and the eastern
Strait of Juan de Fuca. In addition, seas will build to 19 to 23 ft
over the outer Coastal Waters. Additional strong frontal systems
will impact the region through the week ahead. 33

&&

.HYDROLOGY...A series of frontal systems will move through the
area this weekend into early next week and bring several rounds of
precipitation. Widespread river flooding is not likely with minor
rises on area rivers expected. The Skokomish River will rise again
above minor flood stage overnight before briefly dropping below
flood stage Sunday morning. Increasing precipitation around
Christmas and into the end of next week could push the Skokomish
back up to moderate flood stage. For the remaining rivers, the
threat of flooding will also increase in the middle of next week as
ensembles continue to indicate the potential for significant
precipitation area-wide. While discrepancies remain, this most
likely will lead to an increased chance of river flooding becoming
more widespread and landslide concerns that may impact holiday
travel.

&&
.SEW WATCHES/WARNINGS/ADVISORIES...
WA...None.
PZ...Small Craft Advisory until 6 PM PST Sunday for Admiralty Inlet-
     Grays Harbor Bar-Northern Inland Waters Including The San
     Juan Islands-West Entrance U.S. Waters Strait Of Juan De
     Fuca.

     Small Craft Advisory from 4 AM to 6 PM PST Sunday for Central
     U.S. Waters Strait Of Juan De Fuca.

     Gale Warning from 4 AM to 6 PM PST Sunday for East Entrance U.S.
     Waters Strait Of Juan De Fuca.

     Small Craft Advisory until 10 PM PST this evening for Puget
     Sound and Hood Canal.

     Gale Warning until 6 PM PST Sunday 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.

&&

$$