Brier Weather Station
Latitude N 47° 46' 49" Longitude W 122° 16' 48" Elevation 341 ft
988
FXUS66 KSEW 270311
AFDSEW
Area Forecast Discussion
National Weather Service Seattle WA
811 PM PDT Sat Sep 26 2026
.SYNOPSIS...
Zonal flow aloft is contributing to calmer conditions through
this weekend. Another system will arrive on Tuesday for more
rain and breezy winds. Another weak front will arrive on
Thursday. For the late week period into early next week, high
pressure looks favored with thermally induced troughing along
the Oregon coast.
&&
.SHORT TERM /TONIGHT THROUGH MONDAY NIGHT/...
No updates to the forecast this evening. Satellite imagery
shows mostly clear conditions across western Washington with
only mid and upper level clouds streaming through. Highs in the
low 60s for both today and tomorrow. Given the clear skies and
light surface winds, some patchy fog development is possible
overnight into Sunday morning. Whatever develops will generally
dissipate by midmorning. Sunday morning lows will be in the low
40s to upper 30s in the Cascades and adjacent foothills. Despite
the zonal flow, drier afternoon relative humidity is in the
forecast for tomorrow primarily in the mountains. Afternoon RH
minimums in the upper 30 percent range is likely.
Monday now looks generally clear and a couple degrees cooler,
with the next system arriving Monday night into Tuesday from the
northwest.
&&
.LONG TERM /TUESDAY THROUGH SATURDAY/...
Into Tuesday, areas favored for more precipitation
will be the North Cascades, Olympics and areas from King County
north. Breezy winds are forecast for the coast and northern
inland waters. The rain will taper off late Tuesday, for a drier
Wednesday and Thursday. A decaying frontal system may increase
some clouds over the area on Thursday, with little in the way of
meaningful precipitation for that time frame.
High pressure seems favored to return late in the week and over
next weekend. The high will cause thermally induced troughing
over the OR/WA border and increase the high temperatures back
into the upper 60s and possibly low 70s.
21
&&
.AVIATION...
Weak high pressure and offshore flow will lead to
dry and stable conditions across western WA tonight. Pockets of
low clouds and fog are likely around the south sound overnight.
Any fog and/or low clouds will be shallow and dissipate by 18z
Sun. Otherwise, expect VFR conditions on Sunday with mainly high
clouds aloft. 33
KSEA...VFR conditions expected tonight into Sunday with a N wind
around 10 kt. 33
&&
.MARINE...
Weak high pressure and offshore flow tonight. A weak
front will dissipate over the offshore waters on Sunday.
Southerly flow will increase Monday night and Tuesday with a
stronger frontal system. Weak high pressure and offshore flow
will follow on Wednesday. 33
&&
.SEW WATCHES/WARNINGS/ADVISORIES...
WA...None.
PZ...None.
&&
$$
NWS SEW Office Area Forecast Discussion