Area Forecast Discussion
Issued by NWS State College, PA-- Highlight Changed Discussion --
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FXUS61 KCTP 151206
Area Forecast Discussion
National Weather Service State College PA
706 AM EST Sun Jan 15 2017
High pressure over Wisconsin early this morning will build east
into the region today, followed by milder conditions that will
work back into the area for Tuesday. Accompanying the brief warmup
will be periods of rain Tuesday and Tuesday night. The rain should
begin as a few hour period of freezing rain in many locations
throughout Central and Northern Pennsylvania early Tuesday.
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
Regional 11-3.9um Satellite loop shows that most of the earlier,
shallow strato cu has advected south to along the PA/MD border
The moist, sub-freezing air and wet ground, was combining with
a light NW wind (and calm air in some locations) to produce fairly
widespread black ice. A Special Weather Statement (running until
13Z today) highlight this hazard for pedestrians and travelers.
Low temps shortly after sunrise this morning will vary from the
upper teens across the northern tier of PA, to the mid and upper
20s in the south.
High pressure will build into the area from the Western Great
Lakes today, supplying us with fair weather and relatively light
Clear to partly cloudy skies, and a decent amount of sunshine to
start the day (especially across the nrn mtns of PA) will be
topped by a layer of cirrus/cirrostratus streaming in from the
west during the midday and afternoon hours. Mid afternoon high
temps will be in the low to mid 30s across the northern mtns, and
upper 30s to near 40 degrees in the southern valleys.
.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM MONDAY/...
This period will be dry with mainly high clouds tonight, then a
gradual lowering and thickening of the cloud deck Monday
afternoon and night as an upper ridge axis crests over the state.
1032 mb sfc high pressure will be parked between the I-81 and
I-95 corridors in the NE and Mid Atlantic Region overnight
low temps tonight will range from the upper teens over the north,
to the lower and mid 20s across Central and Southern PA.
Highs on Monday will rebound by several degrees in many
locations...varying from the mid 30s to lower 40s.
.LONG TERM /MONDAY NIGHT THROUGH SATURDAY/...
The stubborn trough/upper low over the west coast will weaken and
lift across the southern plains into the Great Lakes region as a
pattern change begins. An upper ridge over the area tries to hold
firm as a warm front lifts through Ohio River Valley early in the
upcoming week. This frontal boundary could be preceded and
accompanied by a light, wintry mix of precip during the early to
mid morning hours Tuesday.
A good portion of the upcoming week is shaping up to be mild and
showery (especially Tuesday) as the bulk of med range guidance
shows a ridge slowly retreating off the East Coast as remnants of
that west coast low get picked up by the northern stream and track
across PA during the midweek.
For Tue into Tue night, deep southerly flow ahead of that trough
will bring a plume of anomalous PWATS over the region which
supports the idea of showery (periods of steady rain on Tuesday)
and mild weather. As has been the case frequently lately, the GFS
brings the trough through faster than the ECMWF. Followed close to
the Nat`l Blend of models vary high, 90-100 pops for Tuesday
surround on either side by mainly likely pops.
Winds turn westerly behind the system as flow turns more zonal,
but with no cold air in sight, temps will remain mild and above
Ridge re-establishes itself over the eastern U.S. for late week,
as mild SW flow persists over the midwest. Guidance suggests
energy will dive south along the west coast eventually helping to
strengthen the building upper ridge over the east. We`ll be on
the eastern side of this, so subtle shortwaves sliding into the
Midwest will bring varying amounts of cloudiness to the west (less
in the east) with low end chances for light showers.
.AVIATION /12Z SUNDAY THROUGH THURSDAY/...
-- Changed Discussion --Vis and cig restrictions early this morning at BFD/IPT/MDT/LNS
will give way to VFR for the remainder the day. VFR continues
for the entire airspace tonight into Monday.
Tue...Sub-VFR likely with freezing rain to rain.
Wed...Sub-VFR possible with rain ending Wed ngt.
Thu...No sig wx.
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