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
874
FXUS61 KCTP 282020
AFDCTP

Area Forecast Discussion
National Weather Service State College PA
320 PM EST Fri Nov 28 2025

.SYNOPSIS...
* Lake effect snow showers will start to wane this evening, but
  may not go away over the northern tier until close to sunrise.
* Brief periods of snow (Northern PA) and a wintry mix (Southern
  PA) are expected late Saturday Night and Sunday with light
  accumulations possible
* A more significant/widespread winter storm is possible on
  Tuesday

&&

.NEAR TERM /THROUGH TONIGHT/...

Immediate concern is the SQW conditions inside each little
cluster/cell of snow crossing the CWA very quickly from the WNW.
Some of the earlier bands were more linear, but the current
character of the precip is very much cellular. Looking off to
the west in OH and wrn PA, this should continue to be the case
at least into the evening. Some striation/consolidation into
bands is expected this evening and overnight.

The closed low over QUE and it`s surrounding trough will be
sliding to the east tonight. The 1000-850 mean flow won`t change
much at all overnight, though, so the exit of LES SNSH is
likely to be a little later than we`d like. They may last all
night across the nrn tier. Model soundings for BFD keep the
cloud depth at least 5kft with the middle to top of the cloud in
the DGZ until nearly sunrise. So, our current expiration time
on the headlines up north (06Z) may need to be adjusted. On the
other hand, though, the inversion is lowering and the dewpoints
aren`t rising, so the SHSN may not be as intense as necessary to
warrant keeping the headlines going. So, for now, we`ll keep
the exp time as is.

The wind and gusts do gradually diminish thru the night as high
pressure starts to move in from the SW. Temps may dip close to
20F in lots of places by morning. The bigger urban areas will be
more in the m20s.

&&

.SHORT TERM /SATURDAY THROUGH SUNDAY/...
The last vestiges of the lake effect clouds and any flurries
should end early in the morning Sat. The upslope low deck in
the west will start to diminish, but high and mid clouds close
up any breaks of sun in the afternoon. The sun in the
southeastern half of the CWA will last thru a good part of the
day. Lift ahead of the next batch of precip will not hold precip
until after dark Sat evening, and perhaps not until close to
midnight, in the NW. The low center is well to our N and the fast
SW flow will pull the precip across the region quickly. The
majority of models and the meso ensembles all make very little
precip for the SE third of the CWA on Sunday. What does manage
to hit the ground there would likely be a mix in the morning or
plain rain from late AM on as temps warm up thru the day. Light
snow will be the predominant precip type for the northern mtns.
The best QPF is in the NW, too. The first swipe at snow totals
there could be near 3 inches in our NW 5-6 counties, and near 2"
in the NE. But, that would be the worst of it as the air is very
dry with little moisture coming in from the Gulf. Very little
signal for freezing rain that lasts more than an hour, but it is
worth mentioning inside the broader collection of "wintry mix."

&&

.LONG TERM /SUNDAY NIGHT THROUGH FRIDAY/...
Unsettled weather will continue into early next week as cold
air in the middle of the country sets up a strong baroclinic
zone over the eastern US. High pressure in the Plains should
keep cold air in place on the northern side of the precipitation
shield from a wave of low pressure progged to move out of the
Gulf of America on Monday. This system should move northeast
around the base of the aforementioned high pressure system,
bringing increasing moisture to the Mid-Atlantic Tuesday into
Wednesday next week. Although it is still too early to pin down
details of timing, intensity, and precipitation type
delineation, the first widespread plowable snowfall of the
season is possible.

The chance for significant (6"+) snowfall amounts appears
limited at this time due the lack of a strong high pressure
center that would help slow the northeastward movement of the
center of low pressure. A relatively quick-moving system could
still bring accumulating snow across a wide footprint, but
high-end amounts would be lower. GEFS and ECENS probabilities
of 6"+ have generally been below 15% over the last several runs. The
track of the low pressure center will also be important for
determining the exact location of the rain/snow transition line. Continue
to monitor the forecast in the days ahead, especially if you
have plans to travel.

High pressure will regain control of our weather in the wake of
the aforementioned system for the middle to end of next week.
Prevailing upper troughing brings high confidence in continued
below normal temperatures and a chilly start to December.

&&

.AVIATION /19Z FRIDAY THROUGH WEDNESDAY/...
Wind flow taking on a more northwesterly direction today. This
will allow lake effect SHSN to pepper KBFD through 29/00Z.
Flight categories will waffle between IFR and MVFR as the snow
bands shift.

Elsewhere, -SHSN will sporadically occur from central PA and
points west...KJST and KAOO, and to a lesser extent...KUNV. Do
not expect an appreciable drop in category as MVFR will persist
with a stratus overcast.

Northwest winds will continue to gust 25 to 30KTS through the
day with occasional wind shear commensurate with those gusts.

Winds will diminish after 29/04Z. A brief break in the adverse
weather on Saturday, before more snow and rain on Sunday and
again on Tuesday, as the weather pattern favors fast moving
weather systems.

Outlook...

Sat...Improving conds; diminishing winds with lingering snow
showers ending.

Sun...Light rain/wintry mix developing from west to east;
restrictions possible. Precip may turn to rain across the south
during the day.

Mon...Mixed/wintry precip likely early on. MVFR likely. IFR
poss.

Tue...More snow possible, before a possible mix later in the
day across the south.

&&

.CTP WATCHES/WARNINGS/ADVISORIES...
Lake Effect Snow Warning until 1 AM EST Saturday for
PAZ004>006.
Winter Weather Advisory until 1 AM EST Saturday for PAZ010-011-
037.

&&

$$

SYNOPSIS...Dangelo/Banghoff
NEAR TERM...Dangelo
SHORT TERM...Dangelo
LONG TERM...Banghoff
AVIATION...Tyburski