315
FXUS66 KSEW 071038
AFDSEW

Area Forecast Discussion
National Weather Service Seattle WA
338 AM PDT Mon Jul 7 2025

.SYNOPSIS...Warm temperatures will continue into Tuesday as a
ridge of high pressure dominates. A weak system will bring a
brief cool down and a chance of light showers on Wednesday before
high pressure rebuilds for the latter part of the week leading to
a return of warmer temperatures and dry conditions.


&&

.SHORT TERM /TODAY THROUGH WEDNESDAY/...A warm day is in store for
western Washington as an upper-ridge traverses overhead.
Subsidence aloft will bring mostly clear skies (after morning
stratus retreats) and increase max temps 7-10 degrees above
average. Temperatures will top out in the lower to upper 80s
throughout the interior with valley locations near 90 F. Coastal
areas are expected to be cooler with values in the 60s. Overnight
lows will fall into the lower 50s to near 60 F with the warmest
temps felt in the Seattle Metro.

The ridge axis will be well east of the Cascades on Tuesday but an
additional warm day is in store. A Moderate (Orange) threat for
HeatRisk must be expressed on Tuesday for the Seattle area as the
previous overnight cooling isn`t expected to be robust. This
level mainly affects those sensitive to heat, especially those
without adequate cooling/hydration. The rest of W WA will see a
Minor (Yellow) threat. A reprieve is on the way however as a
trough and its associated front enters on Wednesday. Temperatures
will cool substantially as light showers return to the area. The
coast and northern half of the Cascades will see the best
probability for the precipitation. Upper 60s to lower 70s are the
features highs for Wednesday.

.LONG TERM /THURSDAY THROUGH SUNDAY/...We`ll be on the backside of
the trough on Thursday as the pattern transitions. While some
lingering clouds and isolated light showers are possible, the
overall trend will be towards partly sunny skies and temperatures
in the 70s for interior areas. Upper level ridging is expected to
rebuild over the region by late week. Temperatures will begin to
climb back into the mid 70s to low 80s across the interior
lowlands. Another weak front might brush the area late next
weekend.

McMillian

&&

.AVIATION...Northwesterly flow aloft will gradually become more
westerly through the day today as upper ridging flattens over the
region. Onshore flow will continue in the low levels. Satellite
imagery shows stratus has pushed inland along the coast and into
the Southwest Interior this morning and is currently making its
way down the Strait of Juan de Fuca. Do not expect for stratus to
make its way into the majority of the interior terminals, however.
Current conditions range from MVFR to IFR for terminals in stratus
to VFR for terminals across the interior. Expect stratus to lift
and scatter by the late morning hours for a return to more
widespread VFR conditions by this afternoon. Surface winds are
primarily out of the north between 4-7 kts this morning, but will
increase to 8-12 kts by this afternoon. Another round of stratus
is likely to make its way inland early Tuesday.

KSEA...VFR conditions will continue through the TAF period. Winds
out of north between 4-7 kts this morning will increase to 8-12
kts this afternoon. Winds will then ease again by this evening.

14


&&

.MARINE...High pressure will persist over the coastal waters
today into early Tuesday. A weak frontal system will then move
into the coastal waters Tuesday night into Wednesday and may bring
a brief uptick in seas. Diurnally driven westerly pushes will
continue along the Strait of Juan de Fuca over the next several
evenings. The push tonight looks to bring small craft strength
wind gusts to the central and eastern Strait. The subsequent
pushes look stronger as onshore flow increases near midweek,
especially in the wake of the front. A weak low pressure system
may move into the area waters on Thursday and will be followed by
high pressure building back into the coastal waters Friday into
the weekend.

Seas will generally persist between 3-6 ft through much of the
week and could become steep at times with persistent northerly
winds over the coastal waters.

14


&&


.FIRE WEATHER...An elevated concern for fire weather must be
expressed for both Monday and Tuesday. An upper-ridge will bring a
period of warm, dry weather as temperatures top out 7-10 degrees
above average for early July. Minimum RHs are expected to bottom
out between 20-30% for locations within Cascade valleys. However,
steady low-level onshore flow looks to bring decent RH recoveries
overnight.

A reprieve will arrive on Wednesday as a weak front enters the
region. Here we`ll see a substantial decrease in temperatures and
an increase in PoPs as light shower activity enters by Wednesday
morning. This system won`t be a washout by any means, but a decent
chance of wetting rain (>0.25") looks favorable for the northern
sections of the Olympics and Cascade with a 30-40% chance.
Localized areas such as Mt. Baker are around 50%. Warmer and drier
weather looks to return towards the second half of the week.

McMillian


.SEW WATCHES/WARNINGS/ADVISORIES...
WA...None.
PZ...Small Craft Advisory from 5 PM this afternoon to 9 AM PDT
     Tuesday for Central U.S. Waters Strait Of Juan De Fuca-East
     Entrance U.S. Waters Strait Of Juan De Fuca.

&&

$$