South Hill, Virginia 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

390
FXUS66 KSEW 160248
AFDSEW

Area Forecast Discussion
National Weather Service Seattle WA
748 PM PDT Sun Mar 15 2026

.SYNOPSIS...
A warm front approaching the coast this afternoon will continue
to move across the region tonight into Monday. Warmer air will
bring snow levels up, bringing a wintry mix of precipitation to
central portions of the Cascades, and rain to the remaining
lowlands. Snow levels will continue to rise through the week,
warming temperatures at the surface, with wet weather continuing
as well through the end of the week.

&&

.SHORT TERM /TONIGHT THROUGH TUESDAY NIGHT/...
The axis of an upper level ridge centered over Washington state
this afternoon will slide southeastward tonight into Monday,
given the region a west-southwesterly flow with a strong jet
streak/atmospheric river aimed at southern British Columbia. A
warm front is approaching from the west this afternoon, and will
move across the region this evening into Monday. Temperatures
have warmed along the coast to where rain will be falling.
Further inland, temperatures this afternoon made it into the 40s
(and even a couple of 50s). The snow levels are expected to rise
tonight into Monday morning as the warm front sweeps through the
state. The lowlands will only see rain with precipitation
tonight/Monday (and through the week). The precipitation falling
in the Cascades this evening is expected to start as snow, and
then transition to freezing rain/wintry mix going into early
Monday morning. Some of the initial bands that move through the
northern Cascades may produce snow rates up to an inch an hour.
For this reason, the winter weather advisory was expected for
tonight to include Stevens Pass (snow threat), with the
potential for up to 6 inches of new snow accumulations. For
Snoqualmie Pass, the advisory expansion was primarily for the
concern of ice accumulations from freezing rain. The pass will
most likely see 0.05-0.10 inches of ice tonight, on top of a wet
slushy 2-4 inches of new snow. Anyone traveling through the
passes tonight should use caution, and watch for potential
slippery spots on roads.

The first round of QPF with the warm front will wrap up Monday
evening, with another round expected to arrive on Tuesday. The
bulk of the precipitation will fall in the Cascades and the
Olympics/Pacific Coast regions. Snow levels will remain high at
8,000-9,000 feet, which will likely cause some runoff from
melting snow/wet soils. Please see the hydrology discussion for
further details on river flooding potential. Temperatures Monday
and Tuesday will be a few degrees warmer, with highs in the mid
to upper 50s (a few low 60s are likely in the south interior). A
few locations in the north interior/coast will see breezy
conditions Monday into Tuesday, with gusts out of the south up
to 25-35 miles per hour.

&&

.LONG TERM /WEDNESDAY THROUGH SUNDAY/...
The models keep the warm and wet pattern going through the week,
with the precipitation scaling back on Friday into next weekend.
The heaviest of the precipitation remains focused in the
Cascades and the Olympics/Pacific Coast, although the amounts in
the second half of the week have dropped slightly. Ensembles are
showing a cooler trend going into next weekend, with some
disagreements into how cool and wet it will be. Nevertheless,
the snow levels will drop from 8,000 feet down to around 3,000
feet next weekend, though with highs likely remaining in the
50s, and the overnight temperatures dropping back into the 30s.

HPR

&&

.AVIATION...
A warm front will clip the area tonight and Monday with westerly
flow aloft. Cigs have been dependent on where the rain is occurring
this evening, as the southern half of the CWA, including SEA, are
reporting VFR conditions while the northern half, starting at PAE,
where the bulk of activity on radar is located is seeing MVFR cigs.
Abundant low-level moisture coupled with more widespread rainfall
overnight will allow for cigs to fall into the MVFR to IFR
throughout the area. FROPA Monday morning will see wind speeds pick
up for the second half of the TAF period with most terminals
forecast to see speeds between 10-15 kts by Monday afternoon. Cigs
will see some improvement as well, with VFR conditions returning.
This FROPA will allow for a brief break in rain, but rain returns
Monday night as the frontal boundary sags south into western WA,
bringing more MVFR conditions. 18/33

KSEA...MVFR cigs just kicked in over the terminal as of 0230Z. Will
monitor for the 03Z amendment, but they may stay there throughout
the overnight period. Remainder of TAF looks to be in good shape
with improved cigs and dry conditions Monday afternoon. Rain will
return Monday night though, so will need to weigh timing to see if
it warrants inclusion in the aforementioned 03Z update. South to
southeasterly winds will persist with speeds 5 kts or less before
ramping up and shifting southwesterly around 12Z...with speeds
generally 8-12 kts expected. 18

&&

.MARINE...
Southerly flow will increase over the waters tonight
and Monday as a warm front lifts north into B.C. Seas will
remain elevated through Tuesday. Southerly flow will prevail
through Thursday generally within 10-20 kt range. The flow will
then flip to northwest or west on Friday behind a cold front. 33

&&

.HYDROLOGY...
River flooding continues for the Chehalis River at Porter which is
cresting at the time of this writing. It is expected to continue to
fall tonight before falling below flood stage Monday. The Chehalis
near Grand Mound fell below flood stage this evening and continues
to trend downward, so that Flood Warning has been cancelled.

Attention then turns to an atmospheric river moving into the region
this week. While the bulk of the moisture will initially move into
British Columbia, it will gradually sag southward into our area by
Tuesday and will bring periods of rain through much of the week.
Higher snow levels and rain on recent snows in the mountains could
bring additional flooding concerns to portions of the area as
several rivers are forecast to rise into Action Stage. For now, the
only river forecast to reach flood stage is the Skokomish River- but
river forecasts will bear watching over the coming days.

&&

.SEW WATCHES/WARNINGS/ADVISORIES...
WA...Winter Weather Advisory until 9 AM PDT Monday for Cascades of
     Whatcom and Skagit Counties.

     Winter Weather Advisory until 2 AM PDT Monday for Cascades of
     Snohomish and Northern King Counties-Cascades of Southern
     King County.

     Flood Watch from Tuesday afternoon through Wednesday afternoon
     for Foothills of the Western and Southern Olympic
     Peninsula-Middle Chehalis River Valley-Olympia and
     Southern Puget Sound-Olympics-Southern Hood Canal-Willapa
     and Black Hills.

PZ...Small Craft Advisory until 5 AM PDT Tuesday 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-West Entrance U.S.
     Waters Strait Of Juan De Fuca.

     Small Craft Advisory from 5 AM Monday to 5 AM PDT Tuesday for
     Admiralty Inlet-East Entrance U.S. Waters Strait Of Juan
     De Fuca-Northern Inland Waters Including The San Juan
     Islands-Puget Sound and Hood Canal.

&&

$$