796
FXUS66 KSEW 130922
AFDSEW

Area Forecast Discussion
National Weather Service Seattle WA
222 AM PDT Sun Jul 13 2025

.SYNOPSIS...Warm and dry conditions will continue through the
weekend with upper level ridging over the region. A brief reprieve
in temperatures is likely on Monday as a system slides southward
from British Columbia and skirts the area. Warmer and drier
conditions are expected again around midweek, with highs potentially
reaching the 90s for some lowland locations.

&&

.SHORT TERM /TODAY THROUGH TUESDAY/...Warm and dry conditions
continue across western WA today with broad high pressure over the
West. Daytime highs in the interior will reach the 80s to lower
90s leading to Moderate HeatRisk. It`ll be cooler along the coast
and in the 60s due to NW onshore winds.

The air mass will be slightly cooler on Monday as a trough drops
down from B.C. Expect highs in the 70s to lower 80s with 60s again
along the coast. Showers with this trough are mainly north of the
border and east of the Cascade crest.

Heights rebuild on Tuesday with strong high pressure now centered
offshore (along 140W). A thermal trough will form along the coast
and the interior will see temps in the 80s to lower 90s again
with Moderate HeatRisk. 33

.LONG TERM /WEDNESDAY THROUGH SATURDAY/...Strong high pressure
will lead to warm and dry weather through Thursday, with elevated
fire weather concerns as well. Temperatures will peak on
Wednesday with interior highs in the 80s and 90s, and lows mostly
in the 60s. The thermal trough will shift inland on Thursday with
broader relief on the coast, but still warm in the interior. A
weak push on Friday brings temperatures closer to average. Same
for the weekend as onshore flow prevails. Still no precip in
sight. 33

&&

.AVIATION...Upper level ridging continues to remain offshore for
northwesterly flow aloft across the area. VFR for all terminals
this morning will continue throughout the period. The exception
being KHQM, where patchy marine stratus may bring brief MVFR/IFR
conditions early this morning. Northerly winds will continue
across the region with generally 8 to 12 knots, with KCLM seeing
more westerly winds 10 to 15 knots later this evening and gusts up
to 20 to 25 kts.

KSEA...VFR this morning will continue throughout the period. N/NE
winds this morning 4 to 8 knots will increase after 20z generally
around 9 to 14 knots, with the potential of some gusts up to 20
kts as well. Northerly winds look to remain elevated throughout
most of the evening.

Mazurkiewicz

&&

.MARINE...Surface high pressure remains offshore with gentle low
level onshore flow throughout the area waters. Diurnally driven
westerly pushes down the Strait will continue over the next
several days. Latest guidance has shown more strength in the
westerly push tonight, therefore have put out a Gale Warning for
the Central and Eastern Strait for this evening. Northerly winds
also look to increase over the coastal waters this evening along
with steep seas, so A Small Craft Advisory has also been issued
for this evening. Thermal troughing looks to build along the
coast through midweek, with periodic increases of northerly winds
through the area waters.

Combined seas 4 to 6 feet look to gradually increase to 8 to 10
feet by early Monday. Seas will likely remain elevated throughout
the first half of the week.

Mazurkiewicz

&&

.FIRE WEATHER...High pressure over the region will maintain warm
and dry conditions across Western Washington this weekend. Modest
onshore flow will provide for excellent overnight recoveries for
most of the lowlands. However, Sunday afternoon will see RH values
dip down into the 25-30% range for areas in the interior. A weak
trough slides through the region on Monday, boosting cloud cover
and humidities, as well as bringing cooler temperatures into the
region. This is a short break as elevated fire weather concerns
return by the middle of next week, with minimum RH values
approaching critical thresholds. While flow remains mostly
northerly or northeasterly, the combination of daytime breezes
overlaying the lowest RHs may elevate concerns around Wednesday
and Thursday for much of Western Washington as a thermal trough
may build over the region. This could further enhance instability
as well. That said, ensemble guidance continues to exhibit a wide
range of potential outcomes for this time period and confidence
remains a bit lower in the details of potential elevated or
critical conditions during the middle to late portion of next
week. Cullen

&&

.SEW WATCHES/WARNINGS/ADVISORIES...
WA...None.
PZ...Gale Warning from 3 PM this afternoon to 6 AM PDT Monday for
     Central U.S. Waters Strait Of Juan De Fuca-East Entrance
     U.S. Waters Strait Of Juan De Fuca.

     Small Craft Advisory from 5 PM this afternoon to 5 AM PDT Monday
     for Admiralty Inlet.

     Small Craft Advisory from 3 PM this afternoon to 7 AM PDT Monday
     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.

&&

$$