Area Forecast Discussion
Issued by NWS Seattle/Tacoma, WA

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FXUS66 KSEW 201001
AFDSEW

Area Forecast Discussion
National Weather Service Seattle WA
301 AM PDT Sun Oct 20 2019

.SYNOPSIS...A weather system will bring showers today. A wetter
frontal system will move through the area Monday and Monday night.
Showers will end on Tuesday as high pressure aloft moves over the
area. Dry weather is expected Wednesday and Thursday then an
upper trough will bring another round of showers on Friday. Dry
weather will return next weekend.

&&

.SHORT TERM /TODAY THROUGH TUESDAY/...An upper short wave in the
northwest flow aloft will bring another round of showers to the
area today. Snow levels will start around 3000-3500 feet and rise
to around 5000 feet in the afternoon. The mountains, especially
higher locations, should pick up a few inches of snow but not
enough for any headlines. It will also be breezy to locally windy
in spots but not enough for any impacts. Highs will be a few
degrees below normal.

After a break between systems tonight, a fairly wet warm frontal
feature will bring rising snow levels and rain to the area Monday
and Monday night. The central Puget Sound area will be a bit rain
shadowed in westerly flow aloft but elsewhere there should be a
pretty good shot of rain. It will also be breezy to locally windy
again at the coast and north interior. Highs will warm to near
normal.

Showers will taper and become confined to the mountains on Tuesday
and then end entirely Tuesday night as upper level ridge builds in
from the west. Schneider

.LONG TERM /WEDNESDAY THROUGH SATURDAY/...Wednesday and Thursday
look dry as an upper ridge crosses the area. An upper trough will
drop down from the northwest on Friday, bringing some showers and
snow to the mountains. This will be a relatively quick shot of
moisture. It looks to dry out again on Saturday with a high
amplitude upper ridge over the Northeast Pacific and dry northerly
flow aloft for Western Washington. Schneider

&&

.AVIATION...A front will move through the area today with another
round of rain and lowering cigs. Once again the mountains and
foothills will become obscured and widespread mvfr cigs and vsby
will develop later this morning. Westerly flow aloft. The air will
be moist and stable today.

KSEA...Rain will develop later this morning as the next front
arrives. Breezy southerly winds will develop this afternoon.

&&

.MARINE...The active weather pattern continues into the first part
of the week. A front will sweep through the area today and yet
another frontal system will affect the region on Monday. Small
craft advisories are in place for all the marine zones and some
areas will see winds rise to 20-30kts. High pressure will build
into the area Tuesday and Wednesday.

&&

.HYDROLOGY...A warmer and fairly wet weather system will cross
the area Monday and Monday night. Two to three inches of rain is
likely for the coast and mountains with local amounts up to fours
inches for the Monday and Monday night timeframe. No flooding is
expected at this time but rivers will likely see sharp rises and
the potential for minor flooding will need to be monitored.
Otherwise, river flooding is not expected for the next 7 days.

&&

.SEW WATCHES/WARNINGS/ADVISORIES...
WA...None.
PZ...Small Craft Advisory until 5 PM PDT 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.

     Small Craft Advisory for rough bar until 4 AM PDT Monday for
     Grays Harbor Bar.

     Small Craft Advisory until 9 PM PDT this evening for Central
     U.S. Waters Strait Of Juan De Fuca-East Entrance U.S.
     Waters Strait Of Juan De Fuca.

     Small Craft Advisory until 11 PM PDT this evening for Northern
     Inland Waters Including The San Juan Islands.

     Small Craft Advisory until 3 PM PDT this afternoon for Admiralty
     Inlet-West Entrance U.S. Waters Strait Of Juan De Fuca.

     Small Craft Advisory from noon today to midnight PDT tonight for
     Puget Sound and Hood Canal.

&&

$$

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