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Area forecast discussion 
National Weather Service Seattle Washington
230 PM PDT Thursday Oct 8 2015

Synopsis...a front will move through the area Friday. Another front
with more rain and locally windy conditions will move through the
area Saturday. A third front will reach western Washington on
Monday. High pressure will build over the area for the middle of
next week.


Short term...a deep low pressure system will move north through the
offshore waters tonight. Most of the rain will head up into British
Columbia but the trailing front will give western Washington some light rain at
times on Friday. Another front will bring heavier rain and some
breezy to locally windy conditions to Saturday. While the front on
Friday weakens and fizzles out...the front on Saturday shows a nice
frontal passage and windshift...and surface high pressure building
in behind it.

Long term...high pressure builds between weather systems for a dry
on Sunday. The last front in the series will reach the area Monday
and that front may linger into Monday night. The 12z GFS stalls this
front over western Washington Monday night and then finally dries up the rain
Tuesday morning. Later Tuesday and more likely by Wednesday dry weather is
expected as high pressure builds over the pacnw.


Aviation...west to southwesterly flow aloft with a flat upper level
ridge over the Pacific northwest. Ceilings have lifted over much of western
Washington...with only kclm still reporting fog and IFR to LIFR
conditions. While ceilings have lifted...Prospect of skies clearing
continues to diminish given current satellite trends. Current tafs
look to reflect this okay...but may have to be lowered slightly for
00z issuance. In addition...given the lingering cloud cover...may
have to revisit expectations for overnight. Current tafs may be a
touch optimistic. Forecast for start of tomorrow seems fine with
ceilings lowering and rain entering the area. May be a touch early on
current tafs...may push back a couple of hours for afternoon
forecast. The air mass will remain moist and stable. Smr

Ksea...middle and high level clouds this afternoon through tonight
ranging sct-bkn. Ceilings will Lower Middle morning tomorrow around 3k feet
in advance of next weather system...with -ra starting right around
noon tomorrow. Winds will remain genreally light for much of the
period...becoming south and increasing in speed to close to 10kt by
late morning.


Marine...nominal southerly winds 10 to 20 knots are expected over the
coastal waters and light winds for the inland waters through this
evening. Remnants of huricane oho will move to the west of the
coastal waters late tonight...bringing gale force winds to the outer
coastal waters by Friday morning as well as large southwesterly
swell for all of the coastal zones late tonight and Friday. Swells
in the 12 to 14 foot range are forecast for the coast. A frontal
system moving through the area on Friday will subsequently bring
Small Craft Advisory winds to the remainder of the coastal zones and
over the northern portion of the area. A second...stronger front
will affect the area Saturday for Small Craft Advisory winds over
all area waters as well as another round of large swell for the
coastal waters. Sunday will see a break followed by a third system
will on Monday.

A marine weather statement has been issued for the large swell
expected to affect the coastal waters going into the Holiday
weekend. Persons going to the coast should use caution when
approaching the surf zone. Cook/smr


Sew watches/warnings/advisories...

Pz...Gale Warning outer coastal waters.
Small Craft Advisory inner coastal waters...northern inland
waters...East Entrance to the Strait and Admiralty Inlet...and
Grays Harbor for rough bar conditions.




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