Brier Weather Station
Latitude N 47° 46' 49" Longitude W 122° 16' 48" Elevation 341 ft
571
FXUS66 KSEW 061751
AFDSEW
Area Forecast Discussion
National Weather Service Seattle WA
1051 AM PDT Mon Jul 6 2026
.SYNOPSIS...
A weak ridge of high pressure will bring warm and dry conditions
to Western Washington into Tuesday. A weak frontal system will
move through on Wednesday with cooler temperatures and a little
rain for parts of the area. Onshore flow will keep temperatures
near normal for the second half of the week with areas of night
and morning clouds.
&&
.SHORT TERM /TODAY THROUGH WEDNESDAY/...
The latest forecast remains on track this morning with no
updates. A weak upper ridge axis is shifting inland this
morning with light northerly flow near the surface. Interior
areas will see several degrees of warming today under mostly
sunny skies. The ridge will begin to weaken tonight in response
to an upper trough moving into the central British Columbia
coast. This will induce a decent onshore push with marine air
and some stratus filtering inland tonight. This will knock
several degrees off high temperatures on Tuesday. A weakening
front is still on track to arrive on Wednesday with further
cooling and a chance of a little rain. Recent model runs are
generally less enthused with rain chances and most of the meager
precip this system stands to produce will be over the Olympic
Peninsula and portions of the North Interior.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/...
The flow aloft turns more or less zonal on Thursday with
weakening post-frontal low level onshore flow. This is a pretty
good recipe for morning clouds, afternoon sun over interior
areas, and high temperatures within a couple degrees or so of
climo. Looking ahead to the remainder of the week, Western
Washington remains locked in the struggle between upper ridging
to our south and an upper trough over British Columbia. This
keeps general onshore flow in place for night and morning clouds
and seasonal temperatures. Another front tries to approach at
the end of the week, but may ultimately result in little more
than an uptick in onshore flow. There are signs at the tail end
of the extended forecast period early next week that strong
upper ridging anchored near the Four Corners region will begin
to exert a little more influence on us...for warmer and drier
conditions. And with mid-July approaching, that story checks out
from a climatological perspective.
27
&&
.AVIATION...
VFR conditions prevail inland with IFR/LIFR at the coast this
morning. These lower ceilings are expected to improve to VFR by
19Z. Forecasts support a return to MVFR ceilings tonight/Tuesday
morning for the coast. There is also a 20-30% probability for
the KSEA area to see MVFR ceilings between 12Z-17Z Tuesday, and
this has been added to the TAF as a scattered layer. Winds will
transition to NW this afternoon and remain in the 5-12 kt range.
Breezy conditions expected along the Strait of Juan de Fuca
this evening with gusts to 25 kt. Surface winds transition to SW
late tonight/early Tuesday morning.
KSEA...VFR expected through the TAF period with a few high clouds at
times. Winds will transition NW this afternoon at 6-9 kt. Winds then
shift SW early Tuesday morning after 08-09z. There is a 20-30%
chance for MVFR ceilings between 12-17Z Tuesday, and this has been
added as a scattered layer through this time.
29
&&
.MARINE...
Broad high pressure over area waters continues to weaken with a
frontal system expected to move over area waters late Tuesday/early
Wednesday. Later on Wednesday high pressure will rebuild in the wake
of the front. Another front will move over area waters late in the
week, weakening high pressure again. Onshore flow will continue
through the Strait of Juan de Fuca throughout the week. Expect small
craft winds through the central and east Strait this evening.
Additionally, winds continue to trend downward for the coastal
waters but seas look to linger around 7-8 ft today with a dominant
period around 7-8 seconds, and thus have extended the advisory
through this evening. Stronger high end small craft westerlies are
likely (70-85% chance) Tuesday and Wednesday evenings. Guidance is
starting to highlight the potential for low-end gales for both
Tuesday and Wednesday evenings. Currently there is a 35-50% chance
on Tuesday and a higher 40-65% chance on Wednesday. Additional small
craft advisories are likely late in the week.
29
&&
.FIRE WEATHER...
Low-level onshore flow will continue through the week. This
will keep good overnight relative humidity recoveries in the
forecast and help subdue fire weather concerns despite somewhat
warmer temperatures through Tuesday. In addition, a weakening
front will move across the area Tuesday night into Wednesday,
bringing the chance for light rain to portions of Western
Washington.
&&
.SEW WATCHES/WARNINGS/ADVISORIES...
WA...None.
PZ...Small Craft Advisory from 2 PM this afternoon to 8 AM PDT
Tuesday for Central U.S. Waters Strait Of Juan De Fuca-
East Entrance U.S. Waters Strait Of Juan De Fuca.
Small Craft Advisory until 5 PM PDT this afternoon for Coastal
Waters From Cape Flattery To James Island 10 To 60 Nm-
Coastal Waters From Cape Flattery To James Island Out 10
Nm-Coastal Waters From James Island To Point Grenville 10
To 60 Nm-Coastal Waters From James Island To Point
Grenville Out 10 Nm-Coastal Waters From Point Grenville
To Cape Shoalwater 10 To 60 Nm-Coastal Waters From Point
Grenville To Cape Shoalwater Out 10 Nm.
&&
$$
NWS SEW Office Area Forecast Discussion