Stevens Pass

000
FXUS66 KSEW 220946
AFDSEW

Area Forecast Discussion
National Weather Service Seattle WA
245 AM PDT Thu Oct 22 2026

.SYNOPSIS...
A dissipating frontal system will spread some clouds across
Western Washington today along with cooler temperatures. High
pressure briefly rebuilds into the region on Friday before an
area of low pressure brings a chance of rain to the area over
the weekend into early next week. Dry conditions return areawide
by the middle of next week.

&&

.SHORT TERM /TODAY THROUGH SATURDAY/...
The last time it was this dry in Seattle three weeks into
October, Michael Jackson, Whitesnake, and Pink Floyd had the top
three albums in the U.S. (1987). And that statistic is likely to
hold at least for a few more days. A weak front will fall apart
as it comes ashore today. We'll see a few clouds and cooler
temperatures today, but that'll be about the extent of it. High
pressure briefly rebuilds into the area on Friday for a little
more in the way of sunshine, but cooler temperatures (really,
just more seasonal) will remain in place. 

Forecast uncertainty starts to ramp later Saturday and beyond.
Anomalously strong upper ridging building into southeastern
Alaska over the weekend will aid in cutting off an upper low 
sliding southward down the British Columbia coast. And the models 
continue to really struggle with the path of the low. In a general 
sense, the ECMWF suite of ensembles are more aggressive with 
bringing some precip to the area and the GFS less so. The NBM is 
something of a compromise and spreads at least a chance of rain to 
the northwest half of the CWA by Saturday evening. 

&&

.LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/...
Most of the forecast area retains at least chance PoPs Sunday
into Monday as the models keep an upper trough over the region
before eventually kicking it eastward. Beyond that, eerily 
quiet conditions are slated to return. Ensemble 500 millibar 
height plots from the Euro, GFS, and Canadian at days 6 through 
8 keep anomalously strong upper ridging over the Gulf of Alaska 
and broad troughing just offshore of California. That's a recipe
for a pretty quiet period of weather here in Western 
Washington.

27

&&

.AVIATION...
Southwesterly flow aloft as a deteriorating front moves through W WA 
today. In the wake of this system, this flow will shift 
northwesterly by tonight and remain that way into Friday. Surface 
winds akin to previous mornings with terminals either reporting 
light and variable winds or favoring a north to northeasterly 
direction with speeds generally less than 5 kts. This afternoon, 
direction is expected to shift more west to southwesterly in the 
wake of the front with speeds increasing to range 5-10 kts.

As with the prior two mornings, much of W WA remains VFR although 
patchy fog has already started to develop, giving rise to isolated 
patches of MVFR, IFR and LIFR conditions. This has already started 
to impact BLI and OLM with rapidly varying conditions, oscillating 
between VFR and IFR/LIFR conditions and, as with prior to mornings, 
cannot rule out that this may impact other terminals on the east 
side of the Sound. That said, forecasts for these terminals have 
TEMPO groups to cover this possibility with timing akin to yesterday 
morning...with the main time of concern between 15-18Z. Although as 
in any fog situation, additional forecast amendments will likely be 
needed to cover this better. Any low clouds will scatter out 18-20z, 
but gradually lowering high and mid clouds through the balance of 
the day. Low stratus likely returns to the area Thursday night with 
stronger onshore low-level flow.

KSEA...VFR at the time of this writing with high clouds present. 
Cannot rule out prospect of a brief arrival of fog and low ceilings 
toward 15z thanks to high cirrus remaining thin. Any low clouds/fog 
that develops is expected to scatter out by 18z with VFR ceilings 
and increasing west surface winds to 10 kt in the afternoon and 
evening hours.

&&

.MARINE...
Wind and seas will increase today as a front moves inland. Highest 
wind and seas will be over the Coastal Waters where a Small Craft 
Advisory remains in effect. Expect building seas to 10-15 ft 
Thursday night. An eye will need to be kept on the western two-
thirds of the Strait, as speeds there may get close to SCA criteria, 
but expecting that they will remain just under. Also for monitoring, 
seas at Grays Harbor Bar may also get close to rough, however 
forecast keeps waves peaking in the 7-9 ft range, again, just shy of 
criteria. 

Winds and seas will ease and subside on Friday. The flow 
will turn offshore this weekend as a deeper surface low spins south 
over the offshore waters. The low will weaken as it moves inland 
early next week. 18/33

&&

.SEW WATCHES/WARNINGS/ADVISORIES...
WA...None.
PZ...Small Craft Advisory from 2 PM this afternoon to 11 AM PDT 
     Friday for Coastal Waters From Cape Flattery To James 
     Island Out 10 Nm-Coastal Waters From James Island To 
     Point Grenville Out 10 Nm-Coastal Waters From Point 
     Grenville To Cape Shoalwater Out 10 Nm.

     Small Craft Advisory from 8 AM this morning to 5 PM PDT Friday 
     for Coastal Waters From Cape Flattery To James Island 10 
     To 60 Nm-Coastal Waters From James Island To Point 
     Grenville 10 To 60 Nm-Coastal Waters From Point Grenville 
     To Cape Shoalwater 10 To 60 Nm.

&&

$$