Mount Walker, Washington Weather Forecast Discussion

000
FXUS66 KSEW 260326
AFDSEW
Area Forecast Discussion
National Weather Service Seattle WA
826 PM PDT Thu Sep 25 2025
.SYNOPSIS...Zonal flow continues through Friday as frontal systems
approach western Washington. Very light shower activity is
possible over the northwest coast on Friday evening into Saturday,
with more widespread rain moving in on Sunday. Unsettled weather
conditions are expected to linger through much of next week with
additional chances for rain.
&&
.SHORT TERM /TONIGHT THROUGH SUNDAY/...A mix of clouds and
clearing this evening as zonal flow continues. Stratus expected
to become more widespread into Friday morning with onshore flow.
In addition, light rain may be possible into Friday, mainly for
Skagit County northwards and along the north coast. No major
forecast updates this evening. Previous discussion below.
Mid and high level clouds are streaming overhead this afternoon
as zonal flow opens the region to frontal systems into the
weekend. Initially, light showers will be prevalent along the
far northwestern coast and in through the San Juan Islands
tomorrow and into Saturday. Accumulations will be light and
generally less than a tenth of an inch. Southwesterly flow aloft
will pick up on Saturday and temperatures will climb slightly
into the 70s before cooling off again on Sunday. More widespread
rain is expected to arrive Sunday morning and persist into the
start of next week. From early Sunday morning through late
Monday night, upwards of a half to three quarters of an inch of
rain is possible throughout the lowlands with one to two inches
in the Olympics and North Cascades. This amount of rainfall will
be extremely beneficial on drought starved foliage throughout
the region.
.LONG TERM /MONDAY THROUGH THURSDAY/...Active weather conditions
are likely to persist through much of the week with additional
rounds of rainfall through Thursday. One forecast element that
will take the next few days for more detail to emerge on is the
possibility for thunderstorms on Monday. It is not in the forecast
presently, but if the low off the coast is to position itself
favorably for moist southerly flow and ample dynamics to reach
western Washington, thunderstorms cannot fully be ruled out. There
are still a lot of forecast details like the position of the low
pressure system to be ironed out, but wanted to mention the
possibility not fully being eliminated. Temperatures will be in
the 60s, with 40s and 50s in the mountains and along the coast.
21
&&
.AVIATION...Westerly flow aloft through Friday as zonal flow
continues. Primarily VFR conditions this evening with areas of
mid level clouds, especially along Hood Canal and northern
Olympic Peninsula. Cigs will lower and stratus will develop into
Friday morning with onshore flow. Areas of MVFR/IFR cigs are
expected around Puget Sound between 10 to 19z Friday, with
localized LIFR cigs, mainly along the coast. Cigs will slowly
improve to VFR with clearing for interior sites in the
afternoon. Light winds tonight will increase from the south on
Friday.
KSEA...VFR conditions this evening with lingering mid clouds.
Stratus will develop tonight into Friday morning. Cigs are
expected to lower to MVFR generally between 13 to 19z. There is
a 65% chance of MVFR cigs during this period, with a 30%
probability of IFR cigs as well. Cigs will then lift and clear
into Friday afternoon. E/NE winds will transition more SE around
06-07z before increasing from the south on Friday. JD
&&
.MARINE...A front sits east of the Cascades, with another frontal
system clipping the northern waters later today. High pressure will
weaken over the coastal waters today as a result. A strong push of
westerlies is expected this afternoon and evening for the
central/east Strait of Juan de Fuca (a small craft advisory was
issued through 11 PM PDT for winds of 15-25 kt). Seas and winds
continue to decrease in the coastal waters with light west winds and
seas at 6-8 ft.
A stronger frontal system will approach the region Friday into the
weekend. Seas will build up to 9-10 ft Saturday (at this time winds
are expected to remain below 20 kt with this frontal system, but
stay tuned to future forecasts as future forecasts will likely
result in increased winds given the expected fall-like nature of
this front). Behind this system, seas will decrease to 6-8 ft next
week, with another system Tuesday into Wednesday potentially
bringing in gusty south winds.
HPR
&&
.SEW WATCHES/WARNINGS/ADVISORIES...
WA...None.
PZ...Small Craft Advisory until 11 PM PDT this evening for Central
     U.S. Waters Strait Of Juan De Fuca-East Entrance U.S.
     Waters Strait Of Juan De Fuca.
&&
$$

NWS SEW Office Area Forecast Discussion