Saint Boniface, Pennsylvania Weather Forecast Discussion

470
FXUS61 KCTP 070905
AFDCTP
Area Forecast Discussion
National Weather Service State College PA
505 AM 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.
* More clouds and a few lake effect rain showers will be found
  today into tonight across the Northwest corner of PA
* The potential for frost moves back into the picture for
  Monday and Tuesday mornings across the typical cold spots in
  northern PA.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
Multi-layered cloud cover and some patchy light rain will linger
into the late morning hours across our far SE counties and the
Western Poconos, beneath the thermally direct, right entrance
region of a 105 kt, swrly upper level jet.
Brief clearing just to the west of this cloud area will likely
fill in quickly with a southeastward expanding area of strato
cu, as the cooler Canadian airmass drifts over the relatively
warm waters of the Glakes. In fact, delta T from the lake (21C
off Erie) to 850 mb (3C) is well over the required 13C for Lake
Effect rain showers. The NBM (because of timing and spatial
differences of the LER bands greatly dampens out the banded
nature and inland extent of the precip.
Measurable precip will make it about as far inland as a
Coudersport to Ridgway line today with a few to several
hundredths of an inch expected. Aside from a sprinkle or two,
the Allegheny Front and Central Ridge and Valley region will
stay dry.
A moderately gusty, west wind and refreshingly low humidity
will make for a perfect fall day.
High temps today will be about the same as Saturday across the
portion of the state between Interstate 81 and I-90, while the
SE counties cool off by about 5 degrees relative to Saturday.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM MONDAY/...
The base of an upper trough will move over the Lower Great Lakes
and PA early tonight, with a fairly rapid change in
orientation, intensity and location of the LER rain bands from
KERI east to the RT 219 corridor as the llvl flow/fetch becomes
more orthogonal to the long axis of Lake Erie. Some multi-band
LER showers will bring an additional few to several hundredths
of an inch of QPF.
Mostly clear skies are on tap for the rest of the Commonwealth
as temperatures trend a bit below average for this time of year.
High pressure will move directly overhead on Monday morning,
bringing high confidence in river valley fog and frost across
northern PA. A few spots could even experience their first
freeze of the year. Frost Advisories will be needed for portions
of northern PA. Lows on Monday morning will range from near
freezing in McKean County to near 50 in the Lower Susquehanna
Valley thanks to ideal radiational cooling conditions and a very
dry airmass (10th percentile PWATs for this time of year).
&&
.LONG TERM /MONDAY NIGHT THROUGH SATURDAY/...
The fall-like pattern will continue through the week ahead.
The airmass moving overhead will be the coolest of the season
so far. Highs in the 60s and 70s will pair with lows in the 30s
to 50s. Frost formation is possible again Tuesday morning for
the typical cool spots in northwest PA with river valley fog
continuing each morning through the end of the week. Abundant
sunshine and dry conditions are favored, with temperatures
gradually increasing each day thanks to a building ridge aloft.
&&
.AVIATION /08Z SUNDAY THROUGH THURSDAY/...
A few, light showers will linger around MDT and LNS through
sunrise, but no reductions are expected. Also toward sunrise, patchy
fog should develop north and west of UNV, but confidence on any
restrictions at BFD, JST, and IPT is low. Cloud cover will
increase over northwest PA towards sunrise and lake effect rain
showers are expected at BFD during the day on Sunday. The rest
of the region will be dry with VFR conditions.
Outlook...
Sun-Mon...Clearing with primarily VFR conditions. Breezy.
Tue-Thur...VFR.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
None.
&&
$$
SYNOPSIS...Lambert/NPB
NEAR TERM...Lambert/NPB
SHORT TERM...Lambert/Banghoff
LONG TERM...Lambert/Banghoff
AVIATION...Gartner/RXR

NWS CTP Office Area Forecast Discussion