047
FXUS66 KSEW 011038
AFDSEW

Area Forecast Discussion
National Weather Service Seattle WA
338 AM PDT Tue Jul 1 2025

.SYNOPSIS...High pressure aloft will continue warm and dry
conditions across the area for the next couple of days.
Temperatures will trend closer to normal by midweek into the
holiday weekend. Most of the region will remain dry through the
weekend, though a few light showers are possible at the coast and
in the mountains.

&&

.SHORT TERM /TODAY THROUGH THURSDAY/...Upper level ridging over
the area this morning resulting in mostly clear skies except for
some marine stratus through the Chehalis Gap and the Strait.
Marine stratus will burn back later on in the morning, with
another warm and dry day on tap for the region. High temperatures
this afternoon will be slightly cooler than the previous day, in
the low 80s for the interior, and mid to upper 60s for areas along
the coast.

The aforementioned upper level ridge will gradually push eastward
into Wednesday with a approaching weak upper trough offshore.
Increasing onshore flow will moderate temperatures through
Thursday into the low to mid 70s for most of the interior, with
locations near the coast in the low to mid 60s. Along with cooler
temperatures, will see a bit more morning clouds across the area
both of these days.

.LONG TERM /FRIDAY THROUGH MONDAY/...Ensemble guidance looks to be
generally agreeing with very weak troughing on Independence Day,
transitioning into more zonal flow forecast pattern into the
weekend. Although confidence is low on exact specifics at this
time, this forecast would reflect some morning clouds and
temperatures close to or slightly above season normals. With this
pattern, this opens the door to the chance of a few light showers
near the northern coast and the North Cascades over the weekend,
although the chance of any precipitation remains fairly low at
this point.

Mazurkiewicz

Some Seattle weather stats as we finish up June and the first
half of the year. Records started at Seattle-Tacoma airport in
1945.

June monthly rainfall total...0.42 inches 5th driest
May and June rainfall 1.25 inches 3rd driest
Half yearly rainfall total 14.36 inches 10th driest
Number of days with measurable rain the first half of the
year...72
Normal number of days with measurable rain 1st half of the
year...87.
 Number of cloudy days ( daily cloud cover 8/10 to 10/10 )
Jan. 1 thru June 30...75.
Normal number of cloudy days Jan 1 thru June 30...122. Felton

&&

.AVIATION...Upper level ridge to the east with weak trough
developing offshore giving southwesterly flow aloft over the area
through Wednesday. In the lower level increasing onshore flow this
afternoon and evening.

Narrow band of IFR stratus right along the coast and moving down
the Strait of Juan de Fuca with high clouds over the southern
portion of the area early this morning.

Stratus only getting as far east as the Lower Chehalis Valley to
the south. Stratus moving through the Strait could move across
Whidbey Island and get close the KPAE this morning. Stratus
dissipating by 18z leaving just some high clouds over the area.

IFR to low end MVFR stratus reforming along the coast 03z-06z
with the stratus moving inland Wednesday morning. Stratus could
get as far east as KSEA by 12z-15z.

KSEA...Just some high clouds at times today. Stratus will be close
to the terminal Wednesday morning 12z-15z. Northeast wind 6 to 10
knots becoming northwest this afternoon. Wind switching to
southwesterly 4 to 8 knots 09z-12z Wednesday. Felton

&&

.MARINE...High pressure will remain in place across the coastal and
offshore waters this week with thermally induced low pressure east
of the Cascades. A weak front will dissipate over the offshore
waters Wednesday.

Diurnal westerly pushes through the Strait of Juan de Fuca each
evening. Gale warning up for tonight for the Central and Eastern
Strait with small craft advisory northwesterlies in Admiralty
Inlet. Small craft advisory westerlies for the Strait Wednesday
night. Late day small craft advisory westerlies possible in the
Strait each evening into the weekend. Felton

&&

.FIRE WEATHER...High pressure over the area will continue to
maintain warm and dry conditions through midweek. Although this
morning we will see modest RH recoveries with the inversion, and
areas west of Puget Sound could see some influence under the
existing marine push. Overall, expect daytime RH values to dip
generally around 30-35% across the Cascades, and central Puget
Sound southward. Winds will be light, generally from the
north/northeast with a slight breeze in the afternoons. A more
deeper marine push on Wednesday will bring cooler temperatures and
better recoveries into the end of the week. Outside of the
uncertainty of any showers developing this weekend in the North
Cascades (20% chance), precipitation is not expected through the
week ahead.

HPR/Mazurkiewicz

&&

.SEW WATCHES/WARNINGS/ADVISORIES...
WA...None.
PZ...Small Craft Advisory until 5 AM PDT early this morning for
     Central U.S. Waters Strait Of Juan De Fuca-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 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-East Entrance U.S. Waters Strait Of
     Juan De Fuca.

     Gale Warning from 6 PM this evening to 3 AM PDT Wednesday for
     Central U.S. Waters Strait Of Juan De Fuca-East Entrance
     U.S. Waters Strait Of Juan De Fuca.

     Small Craft Advisory from 6 PM this evening to 5 AM PDT
     Wednesday for Admiralty Inlet.

&&

$$