Swatara, Pennsylvania Weather Forecast Discussion

334
FXUS61 KCTP 071922
AFDCTP
Area Forecast Discussion
National Weather Service State College PA
322 PM EDT Sun Sep 7 2025
.SYNOPSIS...
* A large area of high pressure builds into the state today and
  brings generally dry conditions with partly to mostly sunny
  and low daytime humidity for at least the next 5 days after
  any early morning valley fog dissipates by 10 AM.
* A few lake effect rain showers will remain possible into the
  evening.
* Clearing skies and light winds will allow for frost formation
  tonight.
&&
.NEAR TERM /THROUGH MONDAY/...
Northwest flow over Lake Erie will keep the potential for a few
lake effect rain showers in place through the rest of the
afternoon and into the first half of the night for far northwest
PA. The rest of the region will continue to see partly cloudy
skies with high temperatures in the 60s and low 70s.
A much drier air mass characterized by PWATs below the 10th
percentile for this time of year will move in overnight as high
pressure builds in from the west. Clearing skies and light winds
will support efficient radiational cooling, with many areas
north and west of the Allegheny Front likely to see temperatures
falling into the mid to upper 30s by early Monday morning.
Frost formation is likely and a Frost Advisory has been issued
for much of the northern and western mountains. There appears to
be at least some potential for portions of McKean County to see
temperatures dip below freezing, but with some lingering
uncertainty regarding how quickly cloud cover decreases, we have
opted against going with a Freeze Warning.
Temperatures will rise quickly after sunrise, ending the risk of
frost by 8 AM. Monday will feature near to slightly below normal
temperatures with highs in the upper 60s and low 70s, along
with mainly clear skies.
&&
.SHORT TERM /MONDAY NIGHT THROUGH TUESDAY NIGHT/...
Another chilly night is expected for Monday night, though frost
potential does not look as widespread as the night before. As of
now, the best chance for frost looks to be limited to McKean
County where temperatures will likely fall into the mid 30s. If
confidence increases in frost potential, another Frost Advisory
may be needed. Dry weather continues on Tuesday, though
temperatures trend a few degrees higher, with most of Central
Pennsylvania seeing highs in the low to mid 70s.
&&
.LONG TERM /WEDNESDAY THROUGH SUNDAY/...
Abundant sunshine and dry conditions are favored into the end of
the week, with temperatures trending warmer for Wednesday
thanks to a building ridge aloft. A weak, moisture-starved cold
front will track through the region Wednesday night into
Thursday, but no sensible weather impacts are expected.
Temperatures may drop slightly for Thursday and Friday behind
this front, but a warming trend is expected into the weekend.
Some guidance shows another shortwave moving through Saturday
night into Sunday, potentially bringing a few showers along with
it, but uncertainty remains high.
&&
.AVIATION /19Z SUNDAY THROUGH FRIDAY/...
A few lake effect showers could affect KBFD today, but dry
conditions will prevail elsewhere. Gusty northwest winds will
continue this afternoon with partly cloudy skies and VFR
conditions.
Valley fog is expected in the river valleys of northern PA
tonight. A brief period of IFR cigs/vis cannot be ruled out at
KBFD, but there is not enough confidence to prevail any
restrictions at this time . Elsewhere, VFR conditions prevail
through the forecast period. Winds will go calm overnight as
high pressure moves overhead.
Outlook...
Mon-Fri...Mainly VFR. Morning valley fog.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
Frost Advisory from 2 AM to 8 AM EDT Monday for PAZ005-006-
010>012-017>019-024-033-037-042-045.
&&
$$
SYNOPSIS...Lambert/Bauco
NEAR TERM...Bauco
SHORT TERM...Bauco
LONG TERM...Lambert/Bauco
AVIATION...Banghoff

NWS CTP Office Area Forecast Discussion