Area Forecast Discussion
Issued by NWS State College, PA

Home | Current Version | Previous Version | Text Only | Print | Product List | Glossary On
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50
000
FXUS61 KCTP 242105
AFDCTP

Area Forecast Discussion
National Weather Service State College PA
405 PM EST Tue Jan 24 2017

.SYNOPSIS...
Storm system lifting into New England tonight with lingering
light snow showers winding down over Pennsylvania. High
pressure and unseasonably mild conditions will briefly return
for Wednesday before another low pressure system brings light
rain for Wednesday night. An associated cold front moves through
late Wednesday night and early Thursday, bringing a push of
colder air along with lake effect snow showers that will linger
into the weekend.

&&

.NEAR TERM /UNTIL 6 AM WEDNESDAY MORNING/...
Winter storm currently tracking up the New England coast with
effects over Central PA continuing to wane. Just light precip
(likely non-accumulating) persisting over northern and parts of
central mountains will taper off completely over next several
hours. NW winds will pick up to around 10-15 mph. Upslope flow
over the west could produce a bit of interest tonight as it
looks like potential for drizzle to develop. Temps may be just
cold enough over parts of the NW mountains for possibly a bit of
freezing drizzle. Chances too low to do anything about it now,
but will have to keep an eye on that through the evening.

&&

.SHORT TERM /6 AM WEDNESDAY MORNING THROUGH WEDNESDAY NIGHT/...
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 as
next system approaches. But, will keep POPs out of the area for
the daylight hours.

Though it will be a light QPF event, PoPs will become quite high
over the NW half of CWA Wed night as low pressure slides in from
the Midwest. PoPs slower to rise over the eastern and southern
portions of CWA as low lifting to the NE as it passes. Overall,
temps remain warm enough for precip to remain all rain through
10z Thu before a cold front brings colder air in from the west
and begins to mix snow in with the rain over the NW mtns.

&&

.LONG TERM /THURSDAY THROUGH TUESDAY/...
All medium range models and EFS are in good agreement and have
been consistent in showing a well-defined pattern change from a
more active and southern stream dominant pattern, to northwest
flow.

A highly amplified/anomalously strong upper ridge and sprawling
sfc high will set up along the West Coast and Great Basin Area
respectively, while several short waves help to carve out a
large scale and highly meridional trough east of the Mississippi
beginning Thursday, and lasting right through the end of this
month.

An initial, then secondary cold front (trailing south from low
pressure over southeastern Canada) will push SE across the
commonwealth on Thursday, with lingering rain showers, mixing
with and changing to snow showers, and becoming more frequent
across the NW mtns during the afternoon and evening.

This pattern change will result in frequent snow showers across
the Alleghenies and Laurel Highlands, with a few to several
inches of snow accum likely accumulating each 48 hour period.
Periods of more significant LES will occur across the Perennial
NW PA snowbelt where some LES Advisories/Watches or even Minimal
warnings may be needed.

Across the central ridge and valley region, expect mostly cloudy
to cloudy skies from stratocu of varying thickness with
flurries and scattered snow showers.

Some periods of sunshine will likely be limited to the Middle
and Lower Susquehanna Valley where just some brief flurries
will fly from time to time.

Thursday and Friday will be the windiest days with gusts likely
in the 25 to 30 kt range both day (and even some higher gusts
possible across the mountains, and to the SE of gaps in the
ridges).

Expect a prolonged period of seasonably cold daytime
temperatures (mainly in the 20s to at times near 30F across the
northern and wrn mtns, and 30s to near 40F elsewhere throughout
the central and southern valleys) with min temps at night
likely a few to several deg F above normal as a result of the
extensive cloud cover in most areas, and periods of breezy/windy
conditions.

&&

.AVIATION /21Z TUESDAY THROUGH SUNDAY/...
Winter storm currently tracking up the New England coast with
effects over Central PA continuing to wane. Just light precip
(likely non-accumulating) persisting over northern and parts of
central mountains will taper off completely over next several
hours. NW winds will pick up to around 10-15 mph and gusty.
Central and eastern areas will see improving ceilings in
downslope flow and should return to VFR this evening. Upslope
flow over the west will keep mainly IFR conditions in place and
could produce a bit of interest tonight as it looks like
potential for drizzle to develop. Temps may be just cold enough
over parts of the NW mountains for possibly a bit of freezing
drizzle.

Conditions improve to VFR areawide (latest in the NW Mtns) on
Wed as high pressure traverses the region. Restrictions spread
in from the west again Wed night as another low pressure system
brings light rain back into the region.

Outlook...

Wed...Low cigs early western 1/2. Otherwise VFR. Breezy late.

Wed night...Light rain moves in from the west. Restrictions
slowly spread from NW to SE.

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

Sat-Sun...MVFR in snow showers west. 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...
None.

&&

$$
SYNOPSIS...RXR
NEAR TERM...RXR
SHORT TERM...RXR
LONG TERM...Lambert/Steinbugl
AVIATION...RXR
CLIMATE...lambert


USA.gov is the U.S. government's official web portal to all federal, state and local government web resources and services.