Area Forecast Discussion
Issued by NWS State College, PA-- Highlight Changed Discussion --
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FXUS61 KCTP 262211
Area Forecast Discussion
National Weather Service State College PA
611 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/...
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 NW 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 CWA 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 /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/MD border. POPs are in the chance range mainly over the NW 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 /22Z WEDNESDAY THROUGH MONDAY/...
-- Changed Discussion --VFR conditions will continue into the evening before ceilings
lower ahead of an approaching warm front and storm system.
Expect reduced conditions at BFD to begin around 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 into Friday.
Fri...AM shrasn/low cigs possible W Mtns.
Sat...SHRA w/IFR CIGs possible N PM. Otherwise no sig wx.
Sun...SHRA w/MVFR cigs N and W. Breezy NW wind.
Mon...No Sig Wx
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