Brier Weather Station
Latitude N 47° 46' 49" Longitude W 122° 16' 48" Elevation 341 ft
931
FXUS66 KSEW 272153
AFDSEW
Area Forecast Discussion
National Weather Service Seattle WA
253 PM PDT Sat Jun 27 2026
.SYNOPSIS...
Unsettled and cooler temperatures expected into next week as
Western Washington remains under the influence of an upper level
trough, resulting in additional weather systems to move over the
area. An upper level ridge may develop over the region next
week, bringing warmer temperatures to the region.
&&
.SHORT TERM /TONIGHT THROUGH MONDAY NIGHT/...
An upper level low continues to move south across Western
Washington this afternoon, bringing scattered showers to the
region. While most showers have remained light, some have
produced moderate radar returns, indicating brief downpours.
Shower chances will continue this afternoon and will gradually
diminish for most of the area, with the exception of the
Cascades, where shower chances will linger into early Sunday
morning. Additionally, there is a slight chance for
thunderstorms this evening. The highest chances are from Olympia
southward, with probabilities at 25-30%. Any thunderstorm that
does develop will be accompanied by heavy rain, small hail,
gusty/erratic winds, and lightning. Lighting chances will
diminish late this evening.
Western Washington will remain under the influence of an upper
level trough into next week. As a result, this will give way for
multiple systems to traverse the region, keeping rain chances
in the forecast. Sunday and Monday looks to remain mostly dry,
with the exception of the Cascades, where there is a 40-60%
chance of showers. Breezy conditions will develop for locations
south/southwest of Seattle Sunday evening with gusts 15-20 mph
possible. Winds will subside early Monday morning. In addition
to rain, temperatures will be on the cooler side. High
temperatures will be in the low 60s along the coast and mid to
upper 60s along the interior.
29
&&
.LONG TERM /TUESDAY THROUGH SATURDAY/...
There is good agreement between long term guidance that the
upper level trough will remain over Western Washington through
at least Friday, keeping cooler temperatures and rain chances in
the forecast. On Saturday, the majority of ensemble members
suggest conditions will become warmer and drier with an upper
level ridge will building offshore and moving inland.
29
&&
.AVIATION...
VFR cigs this afternoon for majority of terminals. Widespread
MVFR cigs expected to return as early as this evening (after
00z) for the coast and Sunday morning (after 12z) for the
interior terminals. There is a slight chance (30%) for IFR cigs
at the coast between 10z-14z. Improvement to VFR expected for
interior terminals after 19z-21z. Scattered showers continue
this afternoon as an upper level low moves through the region.
Expect shower activity to continue into the evening hours. The
majority of showers have remained light, but some have
strengthened and resulted in brief downpours. Additionally,
there is a slight chance of thunderstorms in the region this
afternoon/evening. The highest chances will be from OLM
southwards, where probabilities are 25-30%. Other terminals have
a 10% chance or less. Threats associated with thunderstorm
development include gusty/erratic winds, lightning, small hail,
and heavy downpours. WNW winds this evening will transition back
SW after 06z. Breezy SW winds will develop from SEA southwards
with gusts to 15-18 kt.
KSEA...Lower clouds have moved into the terminal this
afternoon, but still expecting VFR cigs to prevail today. There
is a 40-50% chance for MVFR cigs to return after 13z.
Improvement to VFR likely after 19z. WNW winds this afternoon
through 06z between 6-8 kt. Winds will then shift back SW and
become breezy Sunday evening with gusts to 15 kt possible.
29
&&
.MARINE...
The dominant weather feature will involve broad high pressure
over the Pacific and lower pressure over the interior that will
help promote onshore flow through next week. This will lead to
gusty northwesterlies over the outer coastal waters and steep,
choppy seas. In addition, the central and east portions of the
Strait of Juan de Fuca will likely see diurnally driven
increases in westerlies that may reach small craft advisory
strength. There is a small craft advisory in effect for this
afternoon`s westerlies and it is very likely (85-95%) another
advisory will be needed Sunday evening. The offshore ridge looks
to weaken late next week, resulting in lighting winds and
subsiding seas.
29/27
&&
.FIRE WEATHER...
Little in the way of fire weather concerns remain in the picture
well into the week ahead with upper troughing maintaining cool
conditions, high RH, and periodic chances for shower activity.
Conditions will warm up and dry toward the end of the week as an
upper level ridge builds over the area.
&&
.SEW WATCHES/WARNINGS/ADVISORIES...
WA...None.
PZ...Small Craft Advisory from 5 PM this afternoon to 5 AM PDT
Sunday for Central U.S. Waters Strait Of Juan De Fuca-
East Entrance U.S. Waters Strait Of Juan De Fuca.
Small Craft Advisory until 11 AM PDT Monday 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.
&&
$$
NWS SEW Office Area Forecast Discussion