Area Forecast Discussion
Issued by NWS State College, PA
FXUS61 KCTP 280025
Area Forecast Discussion
National Weather Service State College PA
725 PM EST Mon Feb 27 2017
Return flow around high pressure off the mid-Atlantic coast
will bring milder air into the region through the middle of the
week. Low pressure will move across the Ohio Valley and track
north of Pennsylvania midweek, bringing a rainy period followed
by a potent cold front late Wednesday. Much colder air is in
store for late week, with sub-normal temperatures likely over
.NEAR TERM /UNTIL 6 AM TUESDAY MORNING/...
Still a few sprinkles traversing the Alleghnies this evening as
a weak shortwave slides across the region. Areal coverage is
shrinking as the precip conts to lift into drier air to the
north. Will keep mention of very low pops for central and north
central mtns ...which stand the best bet for seeing sct sprinkles
overnight. Temps will remain about 10F above normals.
.SHORT TERM /6 AM TUESDAY MORNING THROUGH TUESDAY NIGHT/...
Low pressure deepening over the upper midwest Tuesday will push
a warm front into the state bringing showers and perhaps a
thunderstorm or two late day or Tue night. Overall, precip will
be on the light side during this period. Temps on Tuesday will
be another 10F higher than today thanks to the warm advection
and morning sunshine - especially in the south. Readings climb
back into the 50s north/60s south. A very mild night in store
for Tue night as warmer air surges in from the SW ahead of a
potent low pressure system - keeping lows in the 50s most
.LONG TERM /WEDNESDAY THROUGH MONDAY/...
Severe thunderstorm risk is the primary focus on Wednesday with
another strong cold front impinging on a convetive environment
characterized by unseasonably warm temperatures, above normal
PW, relatively low instability and very strong low-to-mid
tropospheric winds. There is still some uncertainty in the
details such as timing and whether CAPE can be realized due to
preceding clouds/pcpn. Despite depicting clear potential for
strong to severe storms given high shear/low cape scenario,
there is still room for adjustments as models begin to converge
on a consensus solution. The key message is preparation for what
could evolve into another damaging thunderstorm wind event. The
threat and risk information have been communicated through the
HWO and social media/decision support channels with updates
coming tomorrow morning with the Day 2 SPC outlook.
It will turn noticeably colder Wednesday night into Thursday as
strong NWLY post-frontal flow directs colder air into the area.
Widespread 30-35 mph wind gusts are probable with 40+mph gusts
possible on the Laurel ridges. The surge of CAA will bring snow
showers downwind of Lake Erie into the NW Alleghenies/Laurels
with minor accumulations (<1 inch) forecast Wed. night into
A broad trough remaining over the Northeast U.S. on Friday will
push off the coast by the beginning of the weekend. A clipper
system associated with the final piece of shortwave energy
embedded in the trough may bring a mix of snow and rain Thursday
night into Friday with a light accumulation possible. The mean
500mb flow is fcst to flatten out a bit over the weekend with
temperatures moderating nicely to above average after bottoming
out on Friday. Overall, the pattern looks fairly quiet over the
weekend and into early next week with another strong frontal
system possible by March 7-8.
.AVIATION /00Z TUESDAY THROUGH SATURDAY/...
Weak shortwave sliding into the area from the west bringing just
enough oomph to kick off very light rain and MVFR conditions
across the southwest this afternoon. MVFR reductions may slip
into KAOO-KUNV for a short time late today, with KBFD having a
better chance for MVFR cigs tonight as light rain area drifts
northward, though by then it will be weakening as wave slips
First half of Tue will bring VFR conditions, with reductions
working in from the west during the afternoon/evening as a warm
front crosses the area bringing light rain.
Tue...Rain showers/Sub-VFR conditions developing from W to E.
Wed...Rain showers/Sub-VFR reductions. Breezy. LLWS likely.
Chance of thunderstorms.
Wed night...Strong FROPA early with gusty winds/tstms.
Thu-Fri...Sub-VFR likely west in sct snow showers. NW winds.
Sat...No sig wx.