Area Forecast Discussion
Issued by NWS Seattle/Tacoma, WA

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FXUS66 KSEW 231040

Area Forecast Discussion
National Weather Service Seattle WA
330 AM PDT Sun Oct 23 2016

.SYNOPSIS...A weak front will move through Western Washington
today for areas of light rain, mainly at the coast. A series of
relatively weak fronts will also bring rain at times during the
upcoming week. Precipitation should be generally light, except for a
stronger system on Wednesday that will bring wetter and blustery


.SHORT TERM...Weak front continues to make its way
gradually northeastward this early morning bringing rain to coastal
zones. Showers ahead of the front still prove to be a nuisance for
locations west of Puget rainfall amounts generally remain
a quarter of an inch or less. Surface low pressure associated with
the front is expected to continue to move practically dead
north...which models indicate will serve to allow the front to
dissipate as opposed to allowing it to make much more progress
eastward. Although the prospect for showers will linger into
tonight...looks like the majority of today may end up generally dry.

A well organized upper level low will remain out over the waters of
the Pacific sending wave after wave of moisture into Western
Washington for the first half of this week. But that low will also
move more in a northerly fashion and as such may limit the eastward
extent of precipitation. The first wave...expected Monday...looks to
have a bit of instability over the waters...and as such may result
in a slight chance for thunder. This instability looks short lived
though...with the threat pretty much over by Monday evening. Tuesday
could see some lingering showers...but the trend is more in line
with today...said lingering showers affecting the area in the
morning hours before giving way to drier conditions.

Inherited forecast looks good and takes the above into account. Very
minimal changes made.  SMR

.LONG TERM...Wednesday looks to prove interesting as yet another
upper level low over the Pacific waters will push a warm front north
over the area. This front is expected to bring rain pretty much area-
wide with QPF values over much of Western Washington getting close
to an inch...albeit either slightly below or slightly above. GFS and
ECMWF disagree on track of this low and the surface low accompanying
it...and this uncertainty will impact the wind forecast. Current
forecast opts to take the road of compromise between the ever-
arguing siblings and suggests some breeziness out there...mainly
along the coast. As would be expected from the previous
analogy...the concept of a consensus for the second half of the week
is laughable. The ECMWF keeps the region in a series of upper level
lows and with them wave after wave of precip while the GFS actually
suggests a bit of a dry period over the area. At this time...have
opted to side more with the GFS...although still keeping low end
chance pops in the the thought of having squishy shoes
for the entire upcoming week feels incredibly unappealing. SMR


.AVIATION...An upper trough will persist around 130W-140W
through tonight then shift east closer to the coast Monday. A weak
front will dissipate over the interior this morning. Low level flow
remaining easterly into Monday.
Ceilings aoa 4000 feet this morning with the exception of some brief
ceilings in the 2000-3000 foot range along the coast. Just mid and
high level cloud cover this afternoon into Monday morning.

KSEA...Ceilings 4000-6000 feet this morning. Just mid and high level
cloud cover this afternoon and tonight. light easterly winds
becoming variable this afternoon. Felton


.MARINE...Weak front dissipating over the inland waters this
morning. Winds will ease this afternoon. A developing 970 mb low
Monday morning will slowly move northward near 130W Monday afternoon
and Monday night, bringing gales to the coastal waters into Tuesday
morning. Another surface low will develop offshore and move
northward Wednesday into Thursday morning with the associated front
moving through the waters later Wednesday into Thursday. Felton


PZ...Gale warning outer coastal waters this evening through
     Monday afternoon.

     Small craft advisory inner coastal waters and west entrance to
     the Strait Monday.

     Small Craft Advisory east entrance to the Strait through this



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