National Weather Service Text Product Display

Area Forecast Discussion
Issued by NWS State College, PA
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573
FXUS61 KCTP 010328
AFDCTP

Area Forecast Discussion
National Weather Service State College PA
1028 PM EST Tue Jan 31 2017

.SYNOPSIS...
A storm system will move east of the region tonight. Upslope
snow showers and flurries will persist over the Laurel Highlands
and Northwest mountains...as west to northwest flow persists
across the region. The mean upper trough over eastern North
America will be reinforced later this week by a series of
shortwaves diving southeast across the Great Lakes.

&&

.NEAR TERM /UNTIL 6 AM WEDNESDAY MORNING/...
Light upslope snow continues to fall over the Allegheny
Plateau, mainly from Clearfield Co northward where visibilities
range from 1 to 2sm at 03Z. Radar showing a back edge to the
steady snow working into extreme NW Pa at 03Z associated with
mid level drying/falling inversion heights, which will work into
the NW Mtns between 04Z-05Z as shortwave passes north of Pa.
Therefore, feel confident that snow will taper off across the
NW Mtns by midnight.

Elsewhere...expect a fairly quiet overnight with lingering
snow/rain showers downwind (east) of the Alleghenies from about
I80 northward. Model soundings showing increasing boundary layer
moisture flowing into the Laurel Highlands toward dawn, so will
increase the chance of light snow down there late tonight.

Temperatures have risen across much of central Pa this evening,
as surface warm front finally pushes through. Portions of the
Mid Susq Valley remain in the cold air at 03Z, but expect a
brief warm up there late this evening. Gusty ssw winds expected
for much of the area the rest of the night, as clipper low
passes north of Pa. The winds should keep temps from falling
much, so have raised overnight mins closer to the latest LAMP
guidance, which shows temps by dawn ranging from the u20s over
the northern Mtns, to the low/mid 30s south.

&&

.SHORT TERM /6 AM WEDNESDAY MORNING THROUGH 6 PM WEDNESDAY/...
The focus for the first half of Wednesday will be over the
Laurel Highlands, where a nearly saturated sfc-700mb ssw flow
ascending the high terrain of Somerset/Cambria counties should
result in a steady light upslope snow between dawn and early
afternoon. Blend of latest model QPF supports accums of around
an inch across this area before the snow diminishes in the
afternoon, as a fast moving shortwave passes east of the region
causing inversion heights to fall. Across northern Pa, a pocket
of cold mid level air, combined with diurnal heating, should
support sct afternoon snow showers. However, with surface temps
mainly above freezing, expect little if any accumulation. Highs
will range from the lower 30s north to the mid 40s southeast.

&&

.LONG TERM /WEDNESDAY NIGHT THROUGH TUESDAY/...
Northwest flow will keep some snow showers across the north and
west into the first part of the weekend. Temperatures will cool
back down closer to normal.

Not seeing much support for snow next Sunday, but have some low
pops in.

Main issue is a large warm up next week. Large spread in model
solutions. The 12Z EC is not quite as extreme as the 00Z EC.

Minor adjustments made to the package. Did lower minimum
temperatures for Wed and Thu night.

&&

.AVIATION /03Z WEDNESDAY THROUGH SUNDAY/...
Improving conditions continue across much of the airspace this
evening with IFR across the north, MVFR central and VFR
southern TAF sites. Some of it will be temporary. Pcpn from
todays clipper/storm system is exiting the region, but
orographic and then Lake Effect induced snow showers will
persist across the NW Mtns and Laurel Highlands through tonight
and likely right into Thursday.

SE/S winds will shift to the west later this evening and become
breezy as CAA keeps restrictions and snow showers confined
mainly to the NW Mtns and Laurel Highlands extending into Thu.

Outlook...

Wed-Thu...Generally VFR...but with MVFR to IFR restrictions in
snow showers in the West and North.

Fri-Sat...VFR, with scattered restrictions in snow showers NW.

Sun...MVfr with chc SW-.

&&

.EQUIPMENT...
KFIG surface observation will be off line for an extended
period of time due to failed power feed to the DCP.

&&

.CTP WATCHES/WARNINGS/ADVISORIES...
Winter Weather Advisory until midnight EST tonight for
PAZ004>006-010-011-017.

&&

$$
SYNOPSIS...DeVoir
NEAR TERM...Fitzgerald
SHORT TERM...DeVoir/Fitzgerald
LONG TERM...Martin
AVIATION...DeVoir/Gartner
EQUIPMENT...
National Weather Service Regional Headquarters
