965
FXUS61 KCTP 251802
AFDCTP

Area Forecast Discussion
National Weather Service State College PA
202 PM EDT Wed Sep 25 2024

.SYNOPSIS...
* Showery weather will persist into Thursday, with perhaps a
  brief break Thursday night  into early Friday
* The remnants of Hurricane Helene will remain well southwest
  of Pennsylvania late this week, though a stationary front
  draped across the Mason-Dixon Line will reintroduce showers
  into the forecast for this weekend.
* Showery weather could continue into early next week, as the
  remnants of Helene very slowly pull away from the region.

&&

.NEAR TERM /THROUGH TONIGHT AND THURSDAY/...
Cloudy, showery weather will persist into tonight and Thursday,
as Central PA remains sandwiched between an upper-level trough
crossing New England and an upper low centered over the Lower
Ohio Valley.

Clouds will keep overnight temperatures mild, with lows in the
upper 50s to mid 60s running about 15 degrees above normal for
late September.

Thursday should be a bit milder than the past few days, with
highs expected to reach the 70s areawide.

&&

.SHORT TERM /THURSDAY NIGHT THROUGH SATURDAY NIGHT/...
The upper-level trough over New England will pull off the
Atlantic Coast Thurs night into Friday, while the remnants of
Hurricane Helene become wrapped up in the upper low over the
Lower Ohio Valley.

At the sfc, a stationary front will become draped across
southern Pennsylvania. We will have to see how the remnant
moisture from Helene interacts with the stationary front. The
presence of this front could keep showers in the forecast into
this weekend, esp across southern PA.

Temperature-wise, the days will see temperatures fairly close
to average, while clouds will keep nighttime temperatures well
above average for early fall.

&&

.LONG TERM /SUNDAY THROUGH WEDNESDAY/...
There is still some uncertainty in regards to how Helene will
impact central Pennsylvania, mainly dependent on interactions
with an upper-level low stationed across the eastern Tennessee
Valley. Deterministic model guidance has outlined that the bulk
of rainfall will stay west of the area while a rather narrow,
negatively tilted upper-level ridge holds strong from the Great
Lakes through the Upper Ohio River Valley. Given the uncertainty
with regards to upper-low interactions, did not deviate much
from continuity and NBM guidance this cycle.

The upper-level low and remnants of the tropical system will
likely drift east across the Commonwealth early next week,
bringing increased chances of shower activity into the beginning
of next week, with highest chances generally across the western
highlands.

&&

.AVIATION /18Z WEDNESDAY THROUGH MONDAY/...
TAFS in good shape overnight, with just some minor adjustments
so far. Main item of interest is the thunderstorm to the
southwest of BFD. Keeping an eye on it, but trend has been
for the storm to weaken. The storm should stay a bit west of
the BFD area.

Main issue today will be MVFR to IFR conditions today into
early Thursday, as a southeast flow of cool, moist air is
advected to the north and west into the mountains.

CIGS will likely not go up a lot today, as showers become more
wide     spread. However, the time of day should aid in CIGS
getting a bit higher.

Any improvement will not last, as CIGS will likely trend back
down some as the sun sets.

Outlook...

Thu...AM low cigs/chc showers, mainly early.

Fri...Patchy AM valley fog possible N Mtns. Chance of showers/low
cigs across the south.

Sat-Sun...Chance of low cigs/showers, mainly across the south.

&&

.CTP WATCHES/WARNINGS/ADVISORIES...
None.

&&

$$

SYNOPSIS...Evanego
NEAR TERM...Evanego
SHORT TERM...Evanego
LONG TERM...NPB
AVIATION...Martin