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fxus61 kctp 112019 
afdctp

Area forecast discussion
National Weather Service State College PA
319 PM EST Mon Nov 11 2019

Synopsis...
developing low pressure in the Ohio Valley will lift northeast
across Pennsylvania tonight, then a deep upper level trough
will swing through the area Tuesday into Wednesday. This will
bring a short lived but very cold air mass into the state on
Tuesday and Wednesday. Look for a warming trend on Thursday and
Friday under sunny skies.

&&

Near term /until 6 am Tuesday morning/...
quiet rest of the afternoon with mild temperatures and precip
remaining west of the County Warning Area. This will change quickly this evening
as band of rain drops into northwest zones. Precip will quickly change
to snow across advisory area which is much closer to colder
air. In the transition there will be a brief period of freezing
precipitation. Elsewhere, precip will sag south and east this
evening and overnight, with thermal profiles well above
freezing.

Across the New York state border quantitative precipitation forecast will be higher /around a third of an
inch/ which supports the current advisory. Elsewhere rain
showers will be light in this low qpf event, and by the time the
colder air arrives the precipitation will essentially be over
before the freezing air aloft arrives. Surface temperatures
will drop rapidly behind the front, with the freezing
temperatures reaching State College by sunrise tomorrow.

&&

Short term /6 am Tuesday morning through Tuesday night/...
northwest flow develops behind the cold front tomorrow which
will produce scattered snow showers in the usual locations
across the northern mountains and Laurel Highlands. Elsewhere
look for a cold and blustery day with temperatures moving
little perhaps even falling during the afternoon.

Expect diminishing lake effect snow showers Tuesday night, as
the upper trough passes east of the state and inversion heights
fall. Look for the coldest temperatures of the autumn by
Wednesday morning in the single digit and teens across a large
part of the area. Of course the areas which receive the fresh
snow will be the coldest.

&&

Long term /Wednesday through Monday/...
no large changes to this part of the package.

Lake effect snow showers will linger into the northwest mountains
and Laurel Highlands into Wednesday morning, perhaps early aft.
This based on how cold the airmass is and the lakes still being
quite warm. Upper level heights come up, but the 2 factors listed
above are big factors for this time of year.

Went back and fourth on Thursday, but ended going back to being
dry after looking at some new data and making a few edits on the
grids.

Next cold front moves in on Friday, but trend is further North.
Heights stay much higher, thus nothing more than maybe a few
snow showers across the north.

Saturday and Sunday look dry.

Monday is largely the superblend. Have some light rain across
the southeast, but amounts will be light if any. Main issue will
be at some point moisture working back to the north off the
ocean, above any remaining cold air.

Overall hints of a pattern change, with more active weather
along or just off the southeast coast.

&&

Aviation /20z Monday through Saturday/...
developing low pressure in the Ohio Valley will lift northeast
across Pennsylvania and push a cold front through tonight, then
a deep upper level trough will swing through the area Tuesday
into Wednesday.

Overall, VFR conditions will continue through this afternoon.
The exception will be over the northwest mountains including bfd where
proximity of a slow moving cold front will keep IFR conditions
right until precipitation arrives later this afternoon.

The front and trough swing across the state tonight, bringing
ceiling reductions through MVFR to IFR to the central terminals
this evening and MVFR to the southeast late tonight. Precip with the
front will start off as rain, but change over to potentially a
short period of freezing rain and then quickly to snow over the
northwest. Precip remains light south of I-80 and east of I-99
so a period of light snow poss there with more minimal impacts.
Wind picks up noticeably from the northwest behind the front, so
speeds after midnight over the northwest will increase to 10-20 mph
while the wind won't pick up over the southeast until around sunrise.

Tuesday will bring potential for scattered snow squalls, mainly
over the northwest mountains and Allegheny plateau. Wind will
remain breezy from the northwest.

Outlook...

Tue...snow showers and squalls with biggest impacts over the northwest
half.

Wed...snow showers with scattered restrictions northwest.

Thu...mainly dry with VFR conditions.

Fri...mainly dry, but a snow shower possible across the north.

Sat...dry with VFR conditions.

&&

Ctp watches/warnings/advisories...
Winter Weather Advisory until 7 am EST Tuesday for paz004>006-
037.

&&

$$

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