Area Forecast Discussion
Issued by NWS State College, PA-- Remove Highlighting --
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FXUS61 KCTP 020748
Area Forecast Discussion
National Weather Service State College PA
248 AM EST Fri Dec 2 2016
A large and deep storm system will move slowly through Quebec over
the next couple of days keeping a prolonged period of cool
northwest flow over the local area. High pressure will build in
for a brief time Sunday before the next frontal system approached
early next week.
.NEAR TERM /UNTIL 6 AM THIS MORNING/...
No big changes late this evening as lake effect regime continues
tonight. Lake clouds and flurries hugging areas along and north of
the PA/NY border this evening are showing a slight southward
drift. Latest HRRR in good agreement with this trend for the
overnight...as backing flow upstream flow evidence in northeast
Ohio should bring this to fruition. Expect an increase in snow
shower activity after midnight across the north. Boundary layer
and sfc marginally cold and bands not expected to become very
organized. However...a light accumulation will be seen over my
northern tier overnight. Some sprinkles still mixed in in areas
where lighter precip rates occur.
Mins will be fairly uniform throughout...ranging from the lower
30s northwest to the lower to middle 30s elsewhere.
.SHORT TERM /6 AM THIS MORNING THROUGH 6 PM SATURDAY/...
The cold NW flow will remain air in place for Friday, but again
the cold air is unimpressive so NW snow shower activity is not
expected to amount to more than nuisance amounts. With high temps
expected to be above freezing, most areas will ave a hard time
making any snow stick at all.
.LONG TERM /SATURDAY NIGHT THROUGH THURSDAY/...
As low continues to move further east into the Canadian Maritimes,
lake effect snow showers over the NW mtns will gradually wind down
on Sat. But one last shortwave Fri night could be enough to extend
snow bands into parts of the central mtns for a time.
Sunday brings a brief respite as high pressure moves over the
state. By late Sunday into the overnight, a period of light snow
is possible as a northern stream shortwave races through the
region with a burst of warm advection. QPF looks to be on the
order of a tenth of an inch or less, but occurring overnight many
places could see their first coating of snow of the young season
by Mon morning.
Another ridge moves through on Monday as progressive weather
pattern becomes more active. On Tues there is decent agreement in
bringing the SW US upper low up through the OHIO Valley as a
shearing out shortwave and diffuse surface low. Unless cold air
damming traps enough chilly air in the low levels to make for some
freezing rain, the precip type with this midwest system looks to
be mainly rain.
The end of the week brings some model disagreement with the
GFS/GEFS being faster than the ECMWF with the next large upper
trof and frontal system. Either way, precip looks like a good bet
around the Thu/fri period as all solutions eventually bring this
trough through. So predictability is increasing, but timing issues
remain. Best bet for precip at this point is mainly rain over the
SE as decent push of warm air lifts ahead of the system, with a
rain/snow mix further north where warm air will not infiltrate as
Behind the trough, looks like a chilly weekend in store with a
potential sharp dropoff in temps.
.AVIATION /07Z FRIDAY THROUGH TUESDAY/...
Early AM satellite loop shows stratocu covering most of Central
Pa associated with slow moving low pressure over Southern Quebec.
07Z radar is showing lake effect snow showers affecting Northwest
Pa, where KBFD is experiencing IFR conditions. Latest GLMP MELD
supports predominantly IFR conditions at KBFD for the balance of
the morning. Elsewhere, model soundings indicate falling CIGs this
morning, as a slight wind shift from WSW to WNW causes moisture
from the Great Lakes to spread south. GLMP MELD suggests IFR
CIGs and snow showers are possible later this morning at KJST.
Downsloping flow east of the mountains should result in
progressively better conditions further east, with tempo MVFR
possible at KAOO/KUNV and VFR at KIPT/KMDT/KLNS.
Weak diurnal heating/mixing should result in a modest increase in
CIGS by this afternoon, likely resulting in CIGS between 1-2KFT at
KBFD/KJST and VFR elsewhere. However, passing snow showers will
still occasionally drop vsbys below 3SM at KBFD/KJST through
The entire region will continue to see breezy conditions last
through the next 24 hours. Clearing skies have resulted in lighter
winds at KMDT/KLNS early this morning. However, Bukfit soundings
support winds between 10-20kts across the entire region later
today and evening, with occasional gusts near 25kts.
Sat...SHSN with ocnl IFR vsby at KBFD/KJST, mainly in the morning.
Sun...Light snow/reduced vis possible at night, mainly NW Mtns.
Mon...No sig wx expected.
Tue...Mixed precip/low CIGs possible.
SHORT TERM...La Corte/Gartner
LONG TERM...La Corte/RXR