Area Forecast Discussion
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FXUS61 KCTP 012049
Area Forecast Discussion
National Weather Service State College PA
349 PM EST Thu Dec 1 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 FRIDAY MORNING/...
Cool west- northwest flow pattern and subsequent cold season
strato- cu clouds will persist into the evening hours.
Clouds will dissipate later this evening especially east of the
central mountains. Near the lakes, snow showers are possible
overnight but no significant accums are expected. Otherwise only a
few sprinkles are expected.
The wind is expected to become a bit more NWLY overnight which
will help bring precipitation more into my NWRN zones.
.SHORT TERM /6 AM FRIDAY MORNING THROUGH 6 PM FRIDAY/...
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 /FRIDAY 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 /21Z THURSDAY THROUGH TUESDAY/...
Through the afternoon, expect persistent MVFR CIGs over the
upslope region from KBFD to KJST and possibly extending into
KUNV/KAOO, and conds across the east. After a brief lull in the
wind speeds this morning over Eastern Pa, expect a rather gusty
daytime, as stronger flow aloft begins mixing to ground level.
Bufkit soundings support frequent gusts to around 25kts across the
entire region later today.
A WSW wind flow should keep lake effect snow showers mainly north
of the border the rest of today. However, latest model data
suggests a slight shift in the wind could cause the lake effect
snow showers to move from upstate NY into NW Pa tonight. Thus, IFR
vis reductions appear possible at KBFD tonight.
Fri-Sat...MVFR CIGS and ocnl SHSN/IFR vis possible KBFD/KJST.
Sun...Slight chance of light snow/reduced vis at night.
Mon...No sig wx expected.
Short Term...La Corte/Gartner
Long Term...La Corte/RXR