Small Craft Advisory 282, NWS Seattle, WA

Area Forecast Discussion
National Weather Service Seattle WA
259 AM PST Thu Nov 24 2016

.SYNOPSIS...Two frontal systems in quick succession will bring
wet and windy weather to Western Washington today and tonight,
with snow in the mountains. There will be a break in the weather
Friday, with an upper trough bringing more rain and mountain snow
Saturday. Another break in the weather is likely Sunday, with the
next front bringing more wet weather Sunday night and Monday.

&&

.SHORT TERM...A strong front is currently bringing rain to the
lowlands, snow to the mountains, and marginal high wind to the
Northwest Interior. The rain and wind will decrease a bit this
morning as the front pushes onshore. Snow will continue over the
mountains much of the day however.

A wave along the front will push up from the south tonight,
increasing rain over the area again. This will also bring more
snow to the mountains. The GFS brings a 999 low across the
Olympics. Other models are weaker or don't have this feature at
all and even the GFS has not been showing much run to run
consistency. For now, the GFS is being somewhat discounted and the
forecast is for breezy to windy weather tonight but nothing more
than advisory levels in some spots.

Friday will see some drying as the frontal band over the area
finally sags south and east of the area. An upper trough will push
into the area Friday night and Saturday, pulling up moisture from
the south and increasing rain chances again. Schneider

.LONG TERM...High pressure aloft will bring a brief dry spell
Sunday but the next front will already be spreading rain into the
area from the west late in the day. Showers should taper on Monday
behind this front with perhaps a dry day Tuesday as an upper ridge
moves over the area. Another front will reach the area Tuesday
night or Wednesday. Schneider

&&

.AVIATION...A frontal system is moving through Western Washington
early this morning. There is strong southwesterly flow aloft. The
air is moist and stable and will become unstable behind the front
later this morning as the areas of rain turn to showers.

KSEA...A front will move through the area this morning. There is
strong south to southwest flow aloft and a breezy southerly
surface wind. Rain with the front will turn to showers with a
frontal passage around daybreak and then another frontal wave should
turn the showers back to rain late in the afternoon or evening.

&&

.MARINE...A strong frontal system early this morning should
be followed by another frontal wave tonight. There are some gale
warnings up early this morning but as the front moves through the
coastal waters the gale warnings there should come down right around
the time the forecast goes out. Another frontal wave will
probably arrive this evening and could give gales to some areas,
but there is also a chance that the stronger gradient will stay to
the south.

&&

.HYDROLOGY...The Skokomish river in Mason county is currently
about a half foot below flood stage. Rains from a front moving
through the area today should push the river above flood stage
late this morning. The river will likely crest tonight and slowly
recede Friday, remaining above flood stage until around Friday
night.

Elsewhere, flooding is not expected during the next 7 days.

&&

.SEW WATCHES/WARNINGS/ADVISORIES...
WA...Winter Storm Warning until 4 AM PST Friday for Cascades of
     Pierce and Lewis Counties-Cascades of Snohomish and King
     Counties-Cascades of Whatcom and Skagit Counties.

     Flood Watch from 7 AM PST this morning through Friday morning
     for Hood Canal Area-Lower Chehalis Valley Area-Olympics.

     High Wind Warning until 10 AM PST this morning for Admiralty
     Inlet Area-San Juan County-Western Skagit County-Western
     Whatcom County.

     Winter Storm Warning until 4 AM PST Friday for Olympics.

PZ...Small Craft Advisory for rough bar until 6 PM PST this evening
     for Grays Harbor Bar.

     Small Craft Advisory until 3 PM PST this afternoon 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.

     Gale Warning until 3 AM PST early this morning 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.

     Gale Warning until 10 AM PST this morning for East Entrance U.S.
     Waters Strait Of Juan De Fuca-Northern Inland Waters
     Including The San Juan Islands.

     Small Craft Advisory until 4 PM PST this afternoon for Admiralty
     Inlet-Puget Sound and Hood Canal-West Entrance U.S. Waters
     Strait Of Juan De Fuca.

&&

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