Area Forecast Discussion
Issued by NWS State College, PA

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FXUS61 KCTP 241200
AFDCTP

Area Forecast Discussion
National Weather Service State College PA
700 AM EST Tue Jan 24 2017

.SYNOPSIS...
A storm off NJ will lift to the northeast today. High pressure
and unseasonably mild conditions will briefly return for
Wednesday before a cold front moves through Wednesday night and
early Thursday. Lake effect snow will then begin and last into
the weekend.

&&

.NEAR TERM /UNTIL 7 PM THIS EVENING/...
Snow band forming over wrn PA has some 40dBz in there. It is
pointed at srn Somerset Co, and snow continues - though light -
over the entire advy area. Have thusly decided to extend the
advy for another 3 hours. While accums won`t be all that much
more, it did not seem right to let the advy expire with snow
actually developing/renewing. HRRR and other hi-res model output
has been doing well predicting the deformation band of precip
over wrn PA. They now paint the snow to linger longest in the NC
mtns, with a bit of a dry slot pushing into Sullivan/Tioga soon.
However, will hold the line on the warning. One report just came
in of 7 or 8 inches in Wellsboro and a few of 5+ in that same
area.

Prev...
Radar loop giving indications that precip (mainly snow) is
becoming lighter. The plume of highest moisture continues to
slide to the north ever so slowly. It is still going to be
pointed into the northeastern mountains through the morning
hours, though. The snow totals up there are already >3" and a
few more hours of snowfall should put them close to or over 6".

Lastest hi-res guidance congeals things into a couple of
generally N-S bands of light snow over wrn and central PA
shortly. I think the radar already hints at this and will follow
closely. Precip rates will be much lighter than overnight,
however, and current expiration time of 12z for the WW advy
should be fine. While some light snow /rain-snow mix in lower
elevs/ is expected into the late morning, there should not be
significant accumulations to warrant extending the advy any
farther in time.

As the snow tapers off, the temps should rise, so any lingering
precip late in the morning or even mid-day could turn back to
rain in the lower elevs. Temps won`t rise much. Not much sun to
be seen. Wind backs more to the west and does increase over the
west and central cos.

&&

.SHORT TERM /7 PM THIS EVENING THROUGH 6 PM WEDNESDAY/...
Upslope flow from the west and cloud temps may create a
drizzly/dreary situation tonight in the western mountains. But,
the west wind should make the downslope magic happen over the
SE - drying things out and keeping it mild through the night.
Temps won`t dip into the 20s in most places. But, a tricky part
to the forecast is where there could be drizzle, there also may
be temps AOB freezing. Will keep this out of the grids for now,
but mention some dz possible in the Laurels/west. If the wind
slackens at all, it could get pretty foggy. But, there should be
enough wind to just make the air be mixed enough to keep the fog
horn in the cartoons.

High pressure does crest over the area Wed AM, and 8H temps
should rise to +4 to +8C across the CWA. Maxes with the
downslope, higher mixing and no snow cover in the SE could be
near 50F, but the snowier places will strain to get above 40F.
Clouds will thicken and lower late in the day over the west.
But, will keep POPs out of most of the area for the daylight
hours. Only the W (esp NW) will have a few sprinkles fall from
mid clouds late in the day as a system moves in quickly from the
west.

&&

.LONG TERM /WEDNESDAY NIGHT THROUGH MONDAY/...
A well-advertised pattern change remains on track from the
second half of the week into the weekend, with high confidence
in a long wave trough carving out over the Eastern U.S. This
will result in a prolonged period of seasonably cold
temperatures and lake effect/high-terrain snow showers during
the remainder of the period. Several inches of snow is probable
in the typical locations like the Lake Erie Snowbelt.

&&

.AVIATION /12Z TUESDAY THROUGH SATURDAY/...
Wide range of conditions expected today. Still some bands of]
snow across northern and western areas. Winds will be on the
gusty side today as well.

Conditions should slowly improve later today, as the storm
pulls away from the area.

Outlook...

Wed...Low cigs/rain possible western 1/2. Breezy late.

Thu-Fri...MVFR/IFR in snow showers west. MVFR to VFR east.

Sat...MVFR/IFR in snow showers west. MVFR to VFR east.

&&

.CLIMATE...
Yes, it snowed over much of the area, but the month of January
is still wayyyy above normal on temperatures. For example, there
have been 13 out of the 23 days this month have been 9 or more
degrees above normal. KIPT is 5.9 degs above normal for the
month so far, and KMDT is 5 degs above normal for the month.

&&

.CTP WATCHES/WARNINGS/ADVISORIES...
Winter Weather Advisory until 10 AM EST this morning for
PAZ005-010>012-017>019-024>026-033-045-046.
Winter Storm Warning until 10 AM EST this morning for PAZ006-
037-041-042.

&&

$$
SYNOPSIS...Dangelo
NEAR TERM...Dangelo
SHORT TERM...Dangelo
LONG TERM...Steinbugl
AVIATION...Martin
CLIMATE...



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