732
FXUS66 KSEW 071013
AFDSEW

Area Forecast Discussion
National Weather Service Seattle WA
313 AM PDT Mon Sep 7 2026

.SYNOPSIS...Low pressure will bring additional showers to
portions of western Washington today, with drier and warmer
weather moving into Tuesday and Wednesday. A pair of systems
will bring more showers and slightly cooler weather toward the
end of the week and into the weekend.

&&

.SHORT TERM /TODAY THROUGH WEDNESDAY/...Broad upper level
troughing remains over western WA today while the upper low
center shifts farther east into ID/MT. For our area, models are
showing showers forming over the North Interior this morning
with isolated to scattered coverage this afternoon in the north
and central sound as a disturbance tracks through. With a
cooler air mass and stronger onshore flow, temperatures will
fall a few degrees below average.

The upper low departs to the N/NE on Tuesday, leaving western WA
dry and mild. The air mass will be a little warmer with highs in
the 70s. The coast will be cooler and in the 60s.

Wednesday will be a few degrees warmer with weak high pressure
and light offshore flow. Highs in the interior will reach the
70s to lower 80s. 33

&&

.LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/...Broad low pressure
over western Canada will sag south and send a trough through
western WA on Thursday. As a result, we`ll see stronger onshore
flow, slightly cooler conditions, and a chance of showers
(mainly in the Cascades). A second system will slowly cross the
area on Friday and Saturday for increasing showers across the
board. The weather looks drier early next week as offshore flow
returns. 33

&&

.AVIATION...VFR conditions with mid to high clouds across most
places in the interior, while MVFR conditions continue along the
coast. Expecting ceilings to deteriorate later this morning to
MVFR across the interior after 12Z. Widespread improvement in
the afternoon after 19Z-21Z. MVFR ceilings return to the coast
tonight. SW flow through this afternoon will transition NW after
22Z-00Z. NE winds tonight.


KSEA...MVFR cigs have arrived slightly earlier than anticipated this
morning. Improvement to VFR after 20Z and the rest of today. SW flow
this morning will transition NW around/after 00Z at 5-7 kt. Winds
will transition NE this evening after 02Z at similar speeds.

29

&&

.MARINE...A Small Craft Advisory continues for the central and
eastern portions of the Strait of Juan de Fuca. Winds should
gradually decrease below thresholds later this morning. Broad
high pressure will slowly build in Monday and strengthen through
the middle of the week. Northwesterly winds will increase over
the coastal waters on Tuesday, but are expected to remain below
small craft thresholds. Stronger northwesterly winds expected
Wednesday afternoon into Thursday. Latest guidance suggests a
35-70% chance for small craft winds over the outer coastal
waters. Additionally, there is a 50-75% chance for small craft
winds through the Strait of Juan de Fuca.

Seas 3-6 feet through Wednesday. Seas will increase to 7-10 feet
towards the end of the week and may get steep at times.

29

&&

.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-East Entrance
     U.S. Waters Strait Of Juan De Fuca.

&&

$$