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fxus66 ksew 142220 

Area forecast discussion
National Weather Service Seattle Washington
320 PM PDT Mon Oct 14 2019

Synopsis...a weak upper level ridge will move eastward and exit
the area by this evening. A frontal system will then approach
western Washington and move inland on Tuesday. Wet and unsettled
weather will then continue through the week and into the weekend as
a series of systems move through.


Short term /today through Wednesday/...current satellite imagery
as well as a look out the window shows the morning low clouds have
burned off revealing mostly sunny skies for most locations over West Washington
this afternoon. The exception to the rule seems to be along the
shores of the central Strait...around Port Angeles...where some low
clouds still linger. The good news is that this patch is slowly
thinning. Temperatures at the time of this writing look to be mostly
in the mid to upper 50s with Bellingham and Seattle hitting 60. All
in all...a nice fall day and given the forecast...the last one for West
Washington for a stretch.

Models still on track for the upper level ridge to continue moving
eastward today with the ridge axis finally crossing the Cascade
crest around midnight tonight. This will hinder the advance of the
incoming frontal system a little...with the front reaching the coast
in the late morning or around noon but models continue to
consistently show this front will have trouble making its way
inland. Most locations should see dry conditions for much of the day
Tuesday before the front finally starts moving eastward late in the
afternoon with the best chances for precip holding off until Tuesday
evening or Tuesday night...depending on location. Once the initial
front works its way in Wednesday morning it appears to begin to
dissipate over the area. Under normal circumstances...this would be
encouraging /unless you like rain/...but a secondary front hot on
its heels passes through Wednesday afternoon and evening. This
second front proves to hold together much better and thus will keep
rain in the forecast for much of the day. This one/two punch in
terms of fronts looks to also bring breezy to windy conditions to
the area. While the strongest winds are expected to be in the usual
favored spots...along the coast and in the north interior...some
spots along the sound will also see some breezes kick up. Models
continue to show wind speeds falling just short of any headline
criteria at this time...but will need to monitor as current solutions
are inching closer to said criteria.

High temperatures here in the short term look to remain mild
generally in the upper 50s to around 60. Overnight lows will see a
significant change though...going from some brisk lower to mid 40s
/and some isolated locations dipping down into the upper 30s/
tonight to upper 40s to lower 50s Tuesday night thanks to the
increased cloud cover as a moderating influence. Smr

Long term /Thursday through Sunday/...late Wednesday night and into
Thursday morning models suggest there may be some scattering out of
precip...the GFS indicating it a bit better than the European model (ecmwf)...but
both models agree that the next frontal system and associated upper
level trough follows so quickly that to even suggest either a break
or brief transition to showers would be folly. Instead...sufficed to
say the wet and active conditions are expected to continue
throughout the extended as a veritable Conga line of systems make
their way through West Washington as upper level low pressure holds court over
the western Canadian coast. This will serve to lower daytime highs
down into the lower to mid 50s for lowland locations but overnight
lows will remain stable in the mid to upper 40s...with some valleys
in the SW interior possibly dipping down into the lower 40s. Smr


Aviation...fair skies will give way to thickening mid and high
clouds on Tuesday. Rain will develop on the coast in the afternoon
with lowering cigs and rain will spread into the interior of western
Washington late in the day--widespread MVFR cigs with local IFR cigs
ought to be in place with the Olympics becoming obscured Tue
afternoon and the Cascades Tue evening.

Ksea...high clouds will arrive and then thicken up and lower into a
mid level deck on Tuesday as a frontal system nears the area. Cigs
will lower additionally Tuesday evening with rain developing. Breezy
southerly winds will arrive with the front later on Tue.


Marine...a strong front will reach the coastal waters by Tuesday
afternoon and there is a Gale Warning in effect. Small craft
advisories are up starting Tuesday afternoon for the inland waters.
Periods of blustery weather will continue Wednesday through Friday
as additional weather systems move ashore in an active weather
pattern. Seas will build along the coast and will be in the 15-20ft
range for much of the latter half of the week.


Hydrology...a series of wet systems moving through the area
Tuesday night into the weekend will cause rivers to rise, but
flooding is unlikely over the next seven days.


Sew watches/warnings/advisories...
Gale Warning from 6 am to 11 PM PDT Tuesday 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 from noon Tuesday to 5 am PDT Wednesday for
Admiralty Inlet-East Entrance U.S. Waters Strait of Juan de
Fuca-northern inland waters including the San Juan Islands-
Puget Sound and Hood Canal.

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