Marysville, Virginia 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

703
FXUS66 KSEW 150326
AFDSEW

Area Forecast Discussion
National Weather Service Seattle WA
826 PM PDT Thu Aug 14 2025


.UPDATE...The forecast remains on track here in this evening`s
update. Latest KATX reflectivity and surface obs are indicative
of a large swath of rain pushing over the coast and into the
Olympics at this hour. This activity is slated to fill over the
interior tonight as showers are already making their way over
Puget Sound and I-5 corridor. Pre-frontal southerly winds will
also pick up with gusts upwards of 20 to 25 mph from Bellingham
south towards the Seattle metro. Overnight lows are to bottom
between the mid 50s to lower 60s. The previous discussion remains
below along with an updated marine section:


&&


.SYNOPSIS...Cool and wet weather is expected late tonight through
Saturday as a strong and moist frontal system pushes through the
northwest. Heavy rain and breezy winds will be the primary impacts
of this system. Conditions will dry out starting Sunday and
through next week more sun and typical summer-like conditions by
the end of next week.


&&

.SHORT TERM /TONIGHT THROUGH SUNDAY/...Relatively calm conditions
today across the area with zonal flow aloft and some patchy low
clouds hanging on from this morning. Temperatures are in the 60s
to low 70s. Temperatures will not warm up much more, with mid 70s
across most of the interior and mid to upper 60s along the coast.
With increasing clouds tonight, lows will be relatively warm, in
the upper 50s to low 60s.

The main feature of the short term will be a frontal system will
move across the area Friday and early Saturday. The system will
have good upper level support from a strengthening upper level
trough currently developing over the Aleutian Islands and into the
Gulf of Alaska. A warm front will move through the area early
Friday morning, with the cold front following behind it Friday
night into Saturday morning. The notable aspect of this system is
the amount of moisture it will be carrying. Precipitable water
values will reach as high as around 1.75", which is almost an inch
above normal and is approaching, if not exceeding, daily record
high values for this time year based on data from UIL. This is
supported by the IVT values in the models, ranging from 500-700
kg/m*s. Long story short, this system will contain a lot of water.
The only main limiting factor is the lack of instability with the
lowest heights and the parent low displaced to the northwest. As
a result, rain rates will likely not be that much of an issue
(except as the main frontal band moves through), but the amount of
rain as a whole is of greater concern. Rain will start out fairly
light and off-and-on through much of Friday morning, with the
main band of heavy rain moving through Friday evening into early
Saturday morning. Through Saturday afternoon, QPF amounts range
from 0.5-1.5" through the interior (lowest in the rain shadow in
the lee of the Olympics from Sequim to Quilcene, highest in
northern interior up to the Canadian border). 2-4" of rain is
expected through the mountains, with peaks up to 5"+ across the
west slopes of the Cascades and North Cascades. This amount of
rainfall will produce hydrologic concerns across the area. These
details are discussed in the hydrology discussion.

In addition to heavy rain, breezy winds will also be a concern
with this system. Southwesterly winds will increase early Friday
morning behind the warm front, peaking Friday afternoon. The
strongest winds will be along the coast and through the northern
interior (north of Everett), with gusts reaching 20 to 30 mph.
Winds decrease Friday night following the cold front passage.
Finally, with the system moving through Friday, temperatures will
be well-below normal with highs in the mid to upper 60s across
much of the area.

Sunday looks to remain mostly cloudy with high temperatures
slightly below average, in the low to mid 70s.

Any near-surface smoke should be pushed out of the area tonight
and the wet and cool conditions should keep any dense smoke to the
immediate vicinity of area fires.

.LONG TERM /MONDAY THROUGH THURSDAY/...Upper level troughing
remains over the Gulf of Alaska through the first half of next
week and mostly zonal flow to weak ridging returns for the second
half of the week. The whole week looks to remain dry, with
morning clouds and perhaps some late-afternoon sun. Sunnier
conditions look more likely Wednesday and beyond. As such,
temperatures will take on a slow warming trend from the low to mid
70s early week to mid to upper 70s by mid week.

62


&&

.AVIATION...Mostly zonal flow aloft this evening into Friday with
perhaps a slight shift to the west-southwest from time to time as an
upper level trough prepares to enter the region. Surface winds
generally southwesterly although some locations may see a wobble to
more southerly from time to time. CLM is continues to see
northwesterly winds thanks to the incoming system pushing air down
the Strait. Speeds ranging 7-11 kts for most terminals although some
are reporting lighter winds on the order of 4-8 kts. Forecast is for
winds to increase as the incoming front approaches between 06-09Z
with speeds generally 10-15 kts and gusts up to 25 kts possible.
These speeds look to persist throughout the remainder of the TAF
period.

High clouds have moved into place over W WA this evening, however
widespread VFR conditions remain in place aside from along the
coast, where the incoming front has already brought cigs down into
IFR. MVFR to IFR conditions will slowly spread eastward tonight with
interior terminals, especially those along the east side of the
Sound, seeing these cigs between 03-06Z tonight. As the front
continues to move into the area, conditions will degrade further as
rainfall moves in with widespread MVFR to IFR cigs expected to be
present throughout the remainder of the TAF period.

KSEA...VFR conditions continue as skies gradually fill in as front
approaches. MVFR conditions emerge overnight as winds increase
around 09Z and cigs will continue to degrade after that. Wind speeds
8-12 kts are expected. Gusts will be possible on occasion, but not
often enough nor with enough confidence for TAF inclusion for
inclusion in the 00Z TAF. Cigs expected to bottom out with precip
around sunrise and afterward. Vis reductions are possible, but
significant ones are not expected at this time.

18


&&

.MARINE...A strong frontal system will approach the region
tonight into Friday. As it crosses over the area waters, southerly
winds will become breezy. A Small Craft Advisory remains in
effect for the coastal waters for the combination of elevated
winds and choppy, steep seas. To go with that, a Small Craft
Advisory remains in effect for the East Entrance of the Strait,
Puget Sound and Hood Canal, Admiralty Inlet, and the Northern
Interior Waters for elevated winds 20 to 25 kts through Friday
evening. Wind gusts may reach up to 35 kts briefly at times
throughout the day on Friday, but are not expected to be frequent
and/or widespread across the waters to warrant a headline upgrade
at this time. Will continue to monitor.

High pressure will briefly build back into the coastal waters on
Sunday before additional weak systems may brush over the area
throughout early next week.

Combined seas building to 6 to 8 feet by Friday morning and continue
throughout the evening. Seas may become choppy/steep throughout
Friday with a dominant period of 7 to 8 seconds before gradually
decreasing to 3 to 5 feet by Monday as high pressure slowly rebuilds
over the waters.

Mazurkiewicz/18


&&


.HYDROLOGY...As mentioned above, a strong and unseasonably moist
frontal system will move across the area Friday into Saturday,
bringing with it a period of heavy rainfall across the area, with
widespread 2-4" with 5-6" possible over the higher peaks. This
system will bring with it a myriad of hydrologic issues. Very dry
antecedent conditions has left area soil moisture values well
below average, which agrees well with our current drought
conditions. That being said, the soils have hardened, which poses
the risk of significant surface runoff. There is uncertainty in
this, however, as the light rain through the first half of Friday
may be enough to make the soil more permeable and curtail some of
the hydrologic impacts of the system.

As mentioned in the hydrologic outlook, the primary impacts will
include: flooding of urban areas and flat agricultural lands, some
small streams and creeks may flood if enough runoff is created,
and a low (but non-zero) probability of impacts to burn scars,
including flash flooding, debris flows, and other falling debris.

While no rivers are forecast to flood, sharp rises are forecast on
area rivers. These rises will pose a threat to anyone engaging in
recreational activities in area rivers, those in or near the
river valleys, and along trails and forest roads.

Heavy rain should end following the frontal passage early Saturday
morning, but high river flows will linger throughout the day on
Saturday.

62


.SEW WATCHES/WARNINGS/ADVISORIES...
WA...None.
PZ...Small Craft Advisory from 9 AM to 11 PM PDT Friday 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.

     Small Craft Advisory from 8 AM to 11 PM PDT Friday 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.

&&

$$