Renton, Virginia 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

199
FXUS66 KSEW 271018
AFDSEW

Area Forecast Discussion
National Weather Service Seattle WA
318 AM PDT Fri Jun 27 2025

.SYNOPSIS...Upper level trough over the area today will move east
tonight. Upper level ridge building over Western Washington this
weekend. The ridge will move east Monday and Tuesday with another
upper level trough arriving Wednesday.

&&

.SHORT TERM /TODAY THROUGH SUNDAY/...Satellite imagery shows
cloudy skies over Western Washington early this morning. Doppler
radar has some light showers from Everett northward. Temperatures
at 3 am/10z were in the 50s.

Last in this series of weak shortwaves, currently near 51N/131W,
will move through the area later today keeping a chance of showers
in the forecast. Highest pops along the north coast with showers
likely. Under mostly cloudy to cloudy skies high temperatures
will once again only be in the 60s. The forecast high of 65 in
Seattle is 8 degrees below normal.

Upper level trough moving to the east tonight. Shower chances
coming to an end over the southern portion during the evening
hours and for the rest of the area overnight. Skies remaining
mostly cloudy keeping lows in the 50s.

Upper level ridge building this weekend. 500 mb heights increasing
from the lower to mid 570 dms at 12z Saturday to the mid 580 dms
00z Monday. Northwesterly onshore gradients continuing through the
period. Afternoon seabreezes will put a cap on the high
temperatures both days. Saturday highs in the mid 60s to mid 70s.
Sunday highs 70s and lower 80s. With the lack of cloud cover low
temperatures a little cooler, in the upper 40s to mid 50s.

.LONG TERM /MONDAY THROUGH THURSDAY/...Extended models in good
agreement Monday and Tuesday with the upper level ridge sliding
east while a weak upper level trough moves into California. High
temperatures peaking Monday in the mid 70s to upper 80s. This will
push the HeatRisk into the moderate category for the warmer
locations like the Southwest Interior and Cascade foothills.
Northwesterly onshore surface gradients turning southwesterly
Tuesday. This combined with the slightly cooler temperatures aloft
as the upper level ridge moves away will cool the highs in the
interior back into the 70s and lower 80s. High temperatures along
the coast will only reach the mid 60s.

Confidence still not very high for Wednesday and Thursday as the
models are having trouble coming up with a consistent solution.
00z runs have a trough moving through the area instead of the
zonal flow aloft that has been present on the last few runs.
Trough not strong enough to produce any precipitation. It will
increase the low level onshore flow resulting in some morning low
clouds and cooler highs, in the mid 60s to mid 70s. Weak upper
level trofiness continuing into Thursday with highs a couple of
degrees above normal. Felton

&&

.AVIATION...Zonal flow aloft continues across Western Washington
today with a weak upper trough over the region. Ceilings are a mixed
bag this morning with widespread MVFR/IFR across the interior from
KPAE northward and along the coast. Predominant MVFR ceilings are
expected across the majority of the region through midday before
lifting to low end VFR away from the immediate coast. Ceilings will
deteriorate back to MVFR most areas by early Saturday as low level
onshore flow continues.

KSEA...Ceilings are expected to congeal into a general MVFR deck
this morning then persist through around 20Z before gradually
lifting to low end VFR this afternoon. Ceilings are expected to fall
back to MVFR after 07Z tonight. Surface winds S/SW 5 to 8 knots
veering W/NW for a period after around 00Z then returning to light
southwesterly overnight tonight.   27

&&

.MARINE...Surface ridging will build over the coastal and offshore
waters into the weekend with lower pressure remaining over the
interior for varying degrees of onshore flow. Thermally induced low
pressure over the interior of Western Washington early next week
should be enough to produce some small craft advisory (or higher)
strength westerly winds in the central/eastern strait.
Unsurprisingly, the standard operational NBM winds used for the wind
grids are far too weak. This will likely be addressed in future
shifts.  27

&&

.SEW WATCHES/WARNINGS/ADVISORIES...
WA...None.
PZ...None.
&&

$$