Brier Weather Station
Latitude N 47° 46' 49" Longitude W 122° 16' 48" Elevation 341 ft
131
FXUS66 KSEW 230325
AFDSEW
Area Forecast Discussion
National Weather Service Seattle WA
825 PM PDT Tue Sep 22 2026
.SYNOPSIS...
Onshore flow will maintain cooler temperatures and cloudy skies
through Thursday, with some drizzle tonight into Wednesday. A
stronger system will bring showers across western Washington
Thursday morning, with more widespread rain later Tuesday into
Friday morning. Cooler and unsettled conditions will continue
through the weekend, with additional chances for precipitation
into next week.
&&
.SHORT TERM /TONIGHT THROUGH THURSDAY NIGHT/...
A weakening front just offshore will spread a few showers into the
Olympic Peninsula overnight, but little in the way of precip will
make it into Puget Sound tomorrow morning. We`ll see one more dry
and seasonable day for the interior on Wednesday before a more
potent system spreads some precip into the region later Thursday
through much of Friday. Current forecasts have this covered. No
updates are planned this evening. Previous discussion follows with
update to the aviation portion. 27
Broad upper level troughing will maintain southwest flow aloft and
onshore flow at the surface over the next few days, with little
change between today and tomorrow. Most of the low stratus from this
morning has eroded under partly cloudy skies, with highs on track to
peak in the mid to upper 60s for most areas. A weak disturbance in
the upper level flow will bring increased clouds and some sprinkles
alongside another marine push. This will bring low clouds and light
showers inland tonight into early Wednesday morning. Conditions will
improve by the afternoon, with cloudy skies lingering and highs once
again generally in the mid to upper 60s.
A warm front will lift northward across the region Thursday
morning, bringing light showers to the region. Forecast models
show some differences in the timing, but a cold front will
follow, bringing in widespread precipitation by the evening.
&&
.LONG TERM /FRIDAY THROUGH TUESDAY/...
Widespread precipitation will move inland through Friday
morning, with most lowland areas seeing roughly half an inch of
rainfall and amounts closer to an inch over the mountains. With
snow levels dropping to 6000-7000 feet on Friday, some of the
higher peaks will even see the first dusting of snow of the
season. Showers will likely continue throughout the day Friday
as the upper level trough axis shifts east of the Cascades.
Forecast models continue to hone in on weak ridging building in
behind on Saturday, which will temporarily bring drier
conditions to western Washington. However, ensembles maintain
chances across the region for more precipitation on Sunday and
into early next week, with cooler-than-normal temperatures
staying in place. Some uncertainty remains in model solutions
early next week, with some breaking apart a frontal system as it
reaches the coast. Regardless, additional rainfall is on the
way, with more fall-like weather settling into place.
15
&&
.AVIATION...
VFR conditions continue this evening across W WA. A weak frontal
system moving into the area late tonight into early Wednesday will
bring another round of lowering ceilings to the area by Wednesday
morning. Most guidance suggests ceilings will range between low-end
VFR to MVFR, though cannot rule out some localized IFR conditions
developing. Light showers will be possible as this system moves into
the area, most likely for terminals along the coast (KHQM) and
Strait (KCLM). KBLI and KOLM may also see some light shower
activity, but overall expect much of the interior terminals to
remain dry as the front breaks up as it moves inland. Southwesterly
winds between 5-10 kt will persist for the majority of the terminals
through this evening before winds ease and become light overnight.
KSEA...VFR conditions are expected to prevail. Ceilings will lower
again on Wednesday morning as a front approaches the terminal,
however guidance continues to keep conditions VFR with the lowest
ceilings remaining around 4000 ft. South to southwest winds will
persist at 5-10 kt into Wednesday.
14/41
&&
.MARINE...
A weak front will move across the area late tonight into
Wednesday with little to no impact expected across the area
waters. Onshore flow will continue with another, weaker push of
westerly winds expected along the Strait of Juan de Fuca this
afternoon and evening. At this time, wind gusts largely look to
remain below 20 kt for the majority of the Strait.
A stronger frontal system will then move through the area waters
Thursday into Friday, bringing an increased likelihood of small
craft winds to the coastal waters and along the Strait of Juan
de Fuca. A third system may approach the waters over the weekend,
but latest guidance shows the system breaking up as it approaches,
so do not expect much in the way of hazardous winds or seas at
this time.
Seas will primarily persist between 5-8 ft through Thursday
before building towards 9-10 ft on Friday in the wake of frontal
system. Seas will then subside towards 4-6 ft over the weekend.
14
&&
.SEW WATCHES/WARNINGS/ADVISORIES...
WA...None.
PZ...None.
&&
$$
NWS SEW Office Area Forecast Discussion