Cross Fork, Pennsylvania Weather Forecast Discussion

123
FXUS61 KCTP 261840
AFDCTP
Area Forecast Discussion
National Weather Service State College PA
240 PM EDT Fri Sep 26 2025
.SYNOPSIS...
* Increasing high clouds overnight, with fog potential across
  the northern tier of Pennsylvania.
* Light rain forecast at times mainly over the southern tier
  this weekend through early next week; heavy rain stays south
  of the region.
* Noticeably cooler, more seasonable temperatures expected as
  the calender flips to October.
&&
.NEAR TERM /THROUGH TONIGHT/...
Recent ECONUS satellite imagery outlines an overall decreasing
cumulus field from this morning with further clearing of the
low-level cloud field progged by recent HREF guidance throughout
the evening as high pressure begins to build into the region.
Despite high pressure influence on the region, an upper- level
low stationed south of the area will allow for high-level clouds
to continue to stream into the region last this evening and
into the overnight hours. Highest impact that the aforementioned
high- level cloud cover has on the current forecast package
will be impacts on fog formation across central Pennsylvania
overnight. Recent model soundings do continue to outline best
fog formation across the northern half of the forecast area with
lower confidence on the extent of fog coverage south and east
of the I-80/I-99 corridor. Low temperatures overnight are
progged by the bulk of model guidance to range from the mid-to-
upper 40s across northwestern Pennsylvania to the lower 60s
across southern portions of the Lower Susquehanna Valley,
generally 5-10F above climatological averages.
&&
.SHORT TERM /SATURDAY THROUGH SUNDAY NIGHT/...
Cloud cover is expected to increase in coverage on Saturday and
continue throughout the weekend with increasingly moist low-
levels in recent model soundings and favorable ascent as an
upper- level low pivots into the Appalachians. This set-up will
allow for favorable moisture returns northward into the Mid-
Atlantic on Saturday, allowing for increased chances for
precipitation across the southern tier of Pennsylvania. At this
time, showers look to be the most probable with best
instability parameters expected to be south of the Mason-Dixon
line throughout the weekend.
Drier conditions are expected on Sunday as high pressure begins
to migrate across the Lower Great Lakes into portions of
central Pennsylvania Sunday morning. High pressure influence on
Sunday will also allow for clearing skies west-to-east on
Sunday, with clear skies for the first half of the overnight
promoting some aspect of radiational cooling and potentially
some valley fog. Some uncertainty in magnitude/coverage of these
impacts on the forecast at this point, as clouds begin to back
fill into the region by daybreak on Monday.
&&
.LONG TERM /MONDAY THROUGH FRIDAY/...
Considerable uncertainty remains into portions of the long-term
with respect to precipitation across the southern reaches of
central Pennsylvania for the first half of next week.
Precipitation across the Carolinas and the south-central
Appalachians will have some potential to track northward into
southern Pennsylvania on Monday and into Tuesday. Recent model
guidance continues to highlight areas south of the region to
have the highest probabilities for higher rainfall, thus have
stuck close to NBM guidance with respect to any rainfall through
the middle of the week with no precipitation expected north of
I-80 and highest chances for precipitation generally south of
the Turnpike.
The northern stream flexes its muscle and drops a 1030+mb high
pressure dome into New England during the middle to second half
of next week. This pattern (higher confidence given run to run
consistency) would spell a noticeable/seasonable cool down along
with dry wx and refreshingly low humidity as the calendar flips
to October. This may also open the door for frost potential
across the northern tier as suggested by the latest NBM min
temps in the mid 30s Wed and Thu night.
&&
.AVIATION /18Z FRIDAY THROUGH WEDNESDAY/...
Widespread VFR expected this afternoon and into late this
evening as slightly drier air works across the airspace. There
is some signal that a broken to scattered deck of MVFR clouds
could develop near BFD.
Outlook...
Sat-Wed...Low confidence in sub-VFR cigs/rain across the
southern/eastern portions of the airspace. Mainly VFR across the
central and northern two thirds of PA.
&&
.CLIMATE...
A record rainfall record was broken on September 25, 2025 in
Johnstown where 1.59 inches of rainfall was observed. This broke
the old record of 1.35 inches set back in 1975.
Heavy rainfall was also observed in State College, where 1.10
inches of rainfall set the third highest rainfall on record for
September 25th. This fell short of 1.98 inches (1975) and 1.18
inches (1977) previously observed at STCP1.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
None.
&&
$$
SYNOPSIS...NPB
NEAR TERM...NPB
SHORT TERM...NPB
LONG TERM...NPB
AVIATION...Gartner/Bowen
CLIMATE...NPB

NWS CTP Office Area Forecast Discussion