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Area forecast discussion 
National Weather Service Seattle Washington
330 am PDT Mon Oct 24 2016

Synopsis...weak fronts will bring a little rain to western
Washington today and Tuesday. A wetter system will move into the
area on Wednesday and linger into Thursday. Drier weather is
possible late in the week.


Short term...current radar does show a few scattered echoes this
morning...but looking at obs from around the to say
conditions are generally dry this early morning.

Models remain pretty consistent depicting upper level low out over
the Pacific waters sending a couple more waves of precip today and
into tomorrow. As has been advertised...the activity looks to be
more while the chance of precip remains in the
forecast for both today and tomorrow...there looks to be occasional
breaks in the action. Surface low pressure associated with this
system looks to have the potential to bring breezy to windy
conditions to the coast and northern interior...with much stronger
winds out over the coastal waters.

That upper low will push up north...only to leave western Washington
in the Thrall of yet another upper level low out over the Pacific.
The warm front associated with the surface low tied into this
feature will creep northward Wednesday morning...proving to be a
significantly wetter feature than what is expected today and
Tuesday. The cold front associated with this system will move
through the region Wednesday night and into Thursday...keeping rain
in the forecast. Smr

Long term...models seem to agree that Friday might see a brief
respite in the rainfall as a pretty progressive ridge pushes through
the area. While both models then bring rain back into the
forecast...the GFS suggests a scenario similar to what has been
observed this past weekend and is expected for the early portion of
the week...where there will be some lingering showers but also the
potential for some breaks. The European model (ecmwf) however paints a far gloomier
and soggier picture. Once again...will guide forecast toward the
more optimistic GFS solution to provide a glimmer of hope. Smr

&& upper trough will persist around 130w-140w
today. Strong S-SW flow aloft. A strong surface low will move
northward about 300 statue miles off the coast today maintaining a
drier offshore component to the low-level wind flow. Mid and high
level cloud cover through today.

Ksea...mid level cloud cover today cigs above 5000 feet. Light
northeast wind becoming easterly this morning and southerly
this afternoon. Felton


Marine...a strong 970 mb low will slowly move northward about 300
miles west of the Washington coast this afternoon and tonight
bringing gales to the coastal waters. As east-southeast gradients peak later
tonight, gales are possible near the East Entrance and northern
inland waters. The low will continue to move north on Tuesday toward
haida gwaii.

Next surface low, a 992 mb low, will track northward inside 130w,
weakening as it makes landfall on northern Vancouver Island
Wednesday night.

Low level flow will turn offshore on Thursday and remain
offshore on Friday. Felton


Sew watches/warnings/advisories...
Pz...Gale Warning until noon Tuesday for coastal waters
from Cape Flattery to James Island 10 to 60 nm-coastal waters
from James Island to Point Grenville 10 to 60 nm-coastal
waters from Point Grenville to Cape Shoalwater 10 to 60 nm.

Gale Warning from 3 PM Monday to noon PDT Tuesday for coastal
waters from Cape Flattery to James Island out 10 nm-coastal
waters from James Island to Point Grenville out 10 nm-
coastal waters from Point Grenville to Cape Shoalwater out
10 nm.

Gale watch from Monday evening through Tuesday morning for
central U.S. Waters Strait of Juan de Fuca-East Entrance
U.S. Waters Strait of Juan de Fuca-northern inland waters
including the San Juan Islands.

Gale Warning from 6 PM Monday to noon PDT Tuesday for West
Entrance U.S. Waters Strait of Juan de Fuca.

Small Craft Advisory for rough bar conditions Grays Harbor
bar late tonight into Tuesday morning.




You can see an illustrated version of this discussion at

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