Area Forecast Discussion
Issued by NWS State College, PA

Current Version | Previous Version | Graphics & Text | Print | Product List | Glossary Off
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

FXUS61 KCTP 131018

Area Forecast Discussion
National Weather Service State College PA
618 AM EDT Tue Mar 13 2018

A potent winter storm storm will track from the mid Atlantic
coast to New Foundland by late tonight. Cold northwest flow will
produce lake effect and upslope snow showers with several inches
of accumulation expected over the Alleghenies. Cold and unsettled
conditions will last through Friday with scattered mountains
snow showers north and west. Drier conditions will try to visit
the region Friday night into Saturday, but another disturbance
dropping in from the midwest will bring at least a small chance
of rain or snow showers Saturday night and Sunday.


Light snow showers finally dissipating across eastern portions
of my CWA as upper trof axis swings eastward. Isolated snow
showers and flurries will peter out by 7 am with little if any
additional accumulations.

Eyes will shift west and northwest as the day wears on, as cold
northwest flow and a fair amount of instability and orographic
lift come together to produce scattered to numerous snow showers
from the Laurels to the northwest mountains. The Laurels may see
this activity punctuated by a heavier burst of snow showers this
afternoon as 50-100J/kg CAPES are advertised by CAMs. For the
above reasons and in collaboration with PBZ/BUF, went ahead and
issued Winter Weather Advisories for Somerset County
(orographic enhancement) and for Warren/McKean Counties (for
lake effect) for this afternoon/tonight through midday
Wednesday/late afternoon Wednesday (respectively).

Over the Alleghenies, the upper trough axis will combine with
orographic forcing to produce scattered to numerous snow
showers, producing a fresh coating overnight in many locations.

NBM/Superblend max temps range from the low 30s over the
Alleghenies, to the low 40s across the Lower Susq Valley. Tight
pressure gradient west of intensifying low over New England
will result in gusty winds, making it feel even colder. Bufkit
soundings support gusts between 20-25kts, with the highest gusts
in the southern half of the state.


Snow showers will continue west and north with additional
accumulations tonight into Wednesday over the Laurels and
Northwest mountains. Steady snow in the cold conveyor belt
wraparound from the instense storm over the offshore New England
waters will bring continued accumualations through Wednesday
evening over the north. Some areas along and north of Route 6
may exceed 8 inches for this duration Advisory event. East of
the mountains, little if any accumulation is expected, but it
will be cold and breezy with a few flurries at times. Mins
tonight will be in the lower to middle 20s with highs Wednesday
ranging from the upper 20s northwest to near 40 southeast.


Persistent blustery northwest flow will keep cold air advection
moving into the region through late week. This will allow for
well below normal temperatures and scattered snow showers
persisting Thu and Fri west and north especially. Couple this
with the gusty winds and wind chills every morning will be in
the teens through Thursday morning. Conditions will improve
late Friday into Saturday with some moderation this weekend
as upper- level ridging across the middle of the country builds
eastward. Another trof undercutting the ridge may spread a
chance of rain or snow showers into central PA Sat night and


Snow over the eastern 1/3 of the airspace trended downward in
intensity after midnight, with visibility improving from IFR to
MVFR/VFR. Pattern is transitioning to a northwest flow regime
with gusty downslope winds from 270-320 degrees supporting
mainly low VFR ceilings and occasional light snow showers and
flurries over the central and eastern 2/3 of the airspace into
late week. The western 1/3 of the airspace will be a different
story with persistent snow showers and prolonged MVFR to IFR
conditions. A few localized snow squalls are also possible over
the western 1/3 of the airspace Tuesday afternoon and included
TEMPO group at KJST/KBFD to show vsby dropping below 1SM.
Expect wind gusts 20-25kts during the day Tuesday through


Tue-Thu...MVFR-IFR in snow showers wrn 1/3; mainly VFR with
occasional MVFR possible in brief snow showers/flurries central
and eastern 2/3.

Fri-Sat...VFR. No sig wx.


Winter Weather Advisory from 8 PM this evening to 8 PM EDT
Wednesday for PAZ004-005.
Winter Weather Advisory until 2 PM EDT Wednesday for PAZ033.


NEAR TERM...DeVoir/Fitzgerald
LONG TERM...DeVoir/Ceru
AVIATION...Steinbugl is the U.S. government's official web portal to all federal, state and local government web resources and services.