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Area forecast discussion 
National Weather Service Seattle Washington
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 (pic0). Showers ahead of the front still prove to be a
nuisance for locations west of Puget Sound rainfall amounts
generally remain a quarter of an inch or less (pic1). 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 (pic2).

A well organized upper level low will remain out over the waters of
the Pacific (pic3) 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 (pic4). This front is expected to bring rain pretty
much area-wide with quantitative precipitation forecast values over much of western Washington
getting close to an inch...albeit either slightly below or slightly
above. GFS and European model (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 European model (ecmwf) keeps the region in a series of
upper level lows and with them wave after wave of precipitation 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 probability of precipitation in the the thought of having
squishy shoes for the entire upcoming week feels incredibly
unappealing. Smr

&& upper trough will persist around 130w-140w
through tonight (pic10) then shift east closer to the coast Monday
(pic11). A weak front will dissipate over the interior this
morning. Low level flow remaining easterly into Monday.
Ceilings at or above 4000 feet this morning with the exception of some brief
ceilings in the 2000-3000 foot range along the coast. Just middle and
high level cloud cover this afternoon into Monday morning.

Ksea...ceilings 4000-6000 feet this morning. Just middle 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 (pic12) and Monday night (pic13), bringing gales to the
coastal waters into Tuesday morning. Another surface low will
develop offshore and move northward Wednesday (pic14) into Thursday
morning with the associated front moving through the waters later
Wednesday into Thursday (pic15). Felton


Sew watches/warnings/advisories...
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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