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Area forecast discussion 
National Weather Service State College PA
227 PM EDT Wed Oct 26 2016

an approaching weather system will bring a cold rain later
tonight into Thursday with a wet snow accumulation possible from
the northern alleghenies into the Poconos. Chilly air will hold
its ground through the end of the work week with some moderation
in temperatures expected for Saturday before a cool down again on
Sunday with overcast skies and a chance of showers.


Near term /through tonight/...
visible and obs showing cloud deck over western PA moving rapidly
eastward with rain not too far behind. Hrrr runs consistently shows
precipitation spreading into northwest zones just before sunset. Precip
initially starts as cold rain but wet bulb and boundary soundings
show a quick transition to a mix or even period of snow for
northern half of state this evening and overnight. Any snow
accumulations expected to be light with surface temperatures a
couple degrees above freezing and precipitation rates slow enough
to prevent significant accumulations...but an inch or so of snow
accumulation closest to nys border is likely. Precipitation will
spread across rest of County Warning Area overnight. South of I-80 temperatures
will be warm enough to remain all rain but it will be close around
I-80 where some mixing is possible for a time.


Short term /Thursday/...
milder air will change any wintry precip to plain rain early on
Thursday for the northern tier. Elsewhere look for a cold rain in
the morning with precipitation decreasing west to east in the
early afternoon. Temperatures will not rise much with most
locations seeing highs in the 40s.


Long term /Thursday night through Tuesday/...
downstream blocking should allow northern stream energy to phase
with the lead trough and eventually result in a negatively tilted
trough over the northeast U.S. By Friday morning. Models show the
formation of a triple point low deepening along the coast into the
Canadian Maritimes by Saturday morning.

A brisk northwest flow may afford some lake enhancement to shower
activity Thursday night and temps are cold enough to mention
rain/snow showers especially in the orographically favored areas
downwind of Lake Erie. Overall the trend should be toward drier
conditions into Friday. The wind gusts may end up being a little
stronger than forecast on the backside of the intensifying low.

High pressure briefly returns later Friday afternoon/evening
before shifting southeast Friday night into Saturday morning as
low pressure tracks across the upper Great Lakes.
Models and ensembles generally agree in bringing a weakening cold
front through the area on Saturday and stalling it out near the
PA/Maryland border. Pops are in the chance range mainly over the northwest 1/2
with little in the way of moisture/qpf. The ec/GFS seem to be
trending toward the idea of a wave of low pressure developing to
the west along the wavy boundary and possibly bringing a better
chance for appreciable rainfall /0.25-0.50 inch/ to southern PA on
Sunday. Beyond Sunday, high pressure dominates the pattern
favoring dry weather.

A noticeable rebound in temperatures appears likely on Saturday
with an ensemble blend yielding highs 10-15 degrees warmer than
Friday. Temperatures may fall back on Sunday before moderating
again into early next week as southerly flow develops ahead of low
pressure in the upper Midwest.


Aviation /18z Wednesday through Monday/...
VFR conditions through this evening before weather system brings
lower cigs and vsbys overnight tonight and for first half of
Thursday. Expect reduced conditions at bfd to begin around 06z
Thursday and then ipt around 09z, unv, jst and aoo around 12z. MDT
and lns are still questionable if the precipitation gets that far
south, however give the moisture and the flow expecting at least
vicinity showers between 12z to 15z Thursday morning.
Precipitation should continue along the boundary through tomorrow
into Friday. So expect intermittent periods of MVFR to IFR cigs
and visibility possible Thursday.

Outlook... shrasn/low cigs possible west mtns.

Sat...rain showers W/IFR cigs possible north PM. Otherwise no sig wx.

Sun...rain showers W/MVFR cigs north and west. Breezy northwest wind.


Ctp watches/warnings/advisories...


near term...Ross
short term...Ross
long term...steinbugl

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