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Area forecast discussion 
National Weather Service State College PA
759 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 /until 6 am Thursday morning/...
broken precip shield entering my northwest counties
now...generally trace amounts having been reported but a recent
hourly amount of .04" over Crawford County...and this enhancement
is now over Forest County.

Hrrr in good agreement with regional radar mosaic on precip
arrival...starting as a cold rain but then transitioning to a mix
with snow and maybe ice pellets...mainly after 03z along the New York/PA
border (mckean and Potter counties). Should see a fairly quick mix
for generally the northern third of the state late tonight and
overnight. Any snow accumulations still 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. Snowprobs indicate 2" amounts possible over
the higher terrain of McKean/Potter/Tioga and Sullivan counties.

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


Short term /6 am Thursday morning through 6 PM 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 Wednesday/...
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 /00z Thursday through Monday/...

Ceilings are continuing to lower ahead of the approaching
front/storm system. VFR conditions will continue into the evening
before lowering to sub VFR around or shortly after midnight.

Expect reduced conditions at bfd to begin by 06z Thursday,
spreading east to ipt by around 09z. Unv, jst and aoo will see
lowering conditions between about 09-12z with MDT and lns
deteriorating around or shortly after sunrise.

Precipitation and sub VFR conditions will should continue along
the boundary through tomorrow and into Friday.

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. sig wx


Ctp watches/warnings/advisories...


near term...Ross/devoir
short term...Ross
long term...gartner/steinbugl corte

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