Area Forecast Discussion
Issued by NWS State College, PA
FXUS61 KCTP 271149
Area Forecast Discussion
National Weather Service State College PA
649 AM EST Mon Feb 27 2017
High pressure off the coast will bring milder air up from the
south through the middle of the week. Low pressure will track
out of the Ohio Valley and north of the area during the middle
of the week bringing a rainy period followed by a potent cold
front late Wednesday. Much colder air is in store for late
week, with sub-normal temperatures likely over the weekend.
.NEAR TERM /UNTIL 7 PM THIS EVENING/...
All is well. Radar returns over the S are well aloft. 20deg
dewpoint depressions are tough to overcome in only an hour. But,
the rain will eventually work it`s way to the surface. Still
chilly, so some flakes are still possible.
clouds ahead of a wave of low pressure moving up from the
southwest will thicken up this morning, but it is very dry at
the surface this morning. The connection to the GOMEX is going
to become thinner through the day as a shortwave over KSTL this
morning zips to about KMDT this evening. This will allow little
development and northward surge of moisture today. There should
be some light rainfall eventually make it to the surface this
afternoon. The temperatures should climb fast enough to keep it
all rain - but will continue to just mention a sprinkle/flurry
possible in the Laurels this morning. The temps are almost up to
freezing at KJST - they have been rising very slightly
overnight. If precip does start to work down, it will take some
time to moisten the llvls up, and some wet-bulb effect plays
into temps/p-type as well. Despite maxes about 10-15F warmer
than Sunday thanks to the srly return flow, the slight wind and
cooling/wet-bulb effect will probably keep it feeling chilly in
the western and central-most counties where rain is likely. The
southwest wind and drying moisture should prevent anything but
a sprinkle in the SE. The deeper moisture creep northward into
the northern mountains late in the day and the south should
.SHORT TERM /7 PM THIS EVENING THROUGH 6 PM TUESDAY/...
Some sprinkles will linger over the northern mountains into the
middle of the night, but most of the area and most of the night
will be dry. Temps should remain about 10F above normals
overnight. Low pressure deepening over the upper midwest
Tuesday will push a warm front into the state and showers and
perhaps a thunderstorm or two are expected in the afternoon.
Temps on Tuesday will be another 10F higher than today thanks to
the warm advection and morning sunshine - especially in the
.LONG TERM /TUESDAY NIGHT THROUGH SUNDAY/...
Prominent southwest to westerly flow will dominate the long term
period with several shortwave trofs dropping into the central
U.S. and providing unsettled weather.
On Wed, an upper wave catches up to the low, bringing a more
significant rainfall and some thunderstorms before a strong cold
frontal passage. Yet another day like Saturday may be in store
on Wednesday with storms before the temperatures drop quickly
after frontal passage with flurries and gusty west winds
replacing the warm air. SPC has the MRGL risk of severe
thunderstorms over all the CTP forecast area and the SLGT risk
nudges up to the Turnpike. Destabilization is the wild-card
here. Have gone just slightly above MOS guidance for maxes on
Wed peering into the recent past and seeing some under-estimated
maxes the past few days.
Colder and very breezy conditions are then in store for late
week in NW flow, along with sct lake effect snow showers in the
NW Mtns. Cooler air lingers into the weekend as upper flow
remains from the NW.
Yet another weather system slides through the Great Lakes over
the weekend, with center of low likely remaining to our north.
The greatest shower chances are over the NW half of the CWA.
.AVIATION /12Z MONDAY THROUGH FRIDAY/...
12Z TAFS sent.
No major changes.
Some high and mid level clouds across the south and west as of
Earlier discussion below.
As expected, a clear but breezy night in some spots at midnight.
LLWS early today at BFD, and IPT, given wind max lifting just
north of the region this morning.
Some mid level clouds today, mainly across the south and west.
Perhaps a brief sprinkle.
Should remain VFR through 00Z Tuesday.
Tue...Rain showers/Sub-VFR conditions.
Wed...Rain showers/Sub-VFR reductions. LLWS poss. Chance of
Wed night...Strong FROPA early with gusty winds.
Thu-Fri...Sub-VFR likely west in sct snow showers. NW winds.