662
FXUS61 KCTP 181857
AFDCTP

Area Forecast Discussion
National Weather Service State College PA
257 PM EDT Mon Aug 18 2025

.SYNOPSIS...
* Seasonably cooler this week with peak summer heat and
  humidity in the rear view mirror
* Little to no rainfall expected through Friday; best rain
  chances on Wednesday and over the weekend
* Refreshing taste of Fall likely to arrive into the last week
  of August

&&

.NEAR TERM /UNTIL 6 AM TUESDAY MORNING/...
Strong high pressure drifting eastward across Ontario and
Quebec will deliver pleasantly cooler and less humid conditions
today. The most refreshing (low dewpoint) air will be across the
northern tier, while the largest 24hr max temp deltas will be
found across the south central ridges through the middle and
lower Susquehanna Valley where easterly flow and low clouds will
help hold highs 10-20 degrees lower vs. yesterday.

Veering and increasingly moist llvl flow to the east/southeast
will maintain and even expand the low stratus overnight. The
upslope flow may even bring some patchy drizzle and/or ridgetop
fog to portions of south central PA. Low temps will range from
50-55F in the northern tier to 60-65F across the south central
ridge/valley region.

&&

.SHORT TERM /6 AM TUESDAY MORNING THROUGH WEDNESDAY NIGHT/...
Low cloud signal prevails to the east of the Allegheny Front on
Tuesday with a spotty shower possible over south central PA.
The cloud cover (with some PM breaks of sun) will again hold
temps in the 70s over the majority of the fcst area.

Shortwave trough diving southeast from the Great Lakes and sfc
wave in the Ohio Valley will bring the "best" chance of rain (in
the next 3 days) on Wednesday -- although QPF output continues
to look rather limited. Low temps Wednesday night should tick
higher by a few degrees with more low clouds.

&&

.LONG TERM /THURSDAY THROUGH MONDAY/...
Increasing confidence in a dry end to the week thanks to large
scale subsidence to the west of departing Hurricane Erin. Rising
heights into the weekend will promote a warming trend with highs
rebounding back into the lower 80s by Friday.

Longer range model and ensemble data continues to show a more
formidable upper trough digging into the Great Lakes and
amplifying this weekend over the Eastern U.S. Moisture
returning northward from the Gulf along the leading frontal
boundary should provide a focus for showers and storms with max
POPs Sat-Sun as it moves slowly eastward from the Appalachians
toward the Mid Atlantic coast.

Taste of Fall on the horizon for at least the first part of next
week as cooler/more refreshing air filters into the region from
Canada.

&&

.AVIATION /19Z MONDAY THROUGH SATURDAY/...
A mid level OVC covers an area east of a KUNV to KAOO line.
Elsewhere SKC. This is in response to a moist low level
easterly flow which will keep KUNV, KAOO, KMDT and KLNS in a
MVFR scenario all day.

All other airfields will will be SKC through the daylight hours
with a light northeast wind.

Clouds will retreat back to the north and west overnight but
then dissipate again tomorrow afternoon. Overall, MVFR to good
VFR will continue for the next 24 hours.

Outlook...

Wed-Fri...Chc of SHRA/TSRA areawide but generally VFR.

&&

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

&&

$$

SYNOPSIS...Steinbugl/Gartner
NEAR TERM...Steinbugl/Gartner
SHORT TERM...Steinbugl
LONG TERM...Steinbugl
AVIATION...Tyburski