884
FXUS61 KCTP 290725
AFDCTP

Area Forecast Discussion
National Weather Service State College PA
325 AM EDT Sun Jun 29 2025

.SYNOPSIS...
* Widespread fog over much of central PA this morning.
* Today will be the best day of the final weekend of June with
  lower humidity and mostly rain-free/dry conditions (slim
  shower/storm chances in southern PA).
* Stormy pattern resumes early week with renewed risk of strong
  to severe storms and locally heavy rainfall.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
Widespread fog in place across a good chunk of central PA this
morning, although not seeing much in the way of dense fog
currently. Still plenty of time to see lowering visibilities
through sunrise in a saturated airmass. However, drier air
working into the northern tier, evidenced by dewpoints in the
mid-upper 50s, and more concentrated cloud cover farther south
may limit more widespread dense fog.

Surface high pressure building into central PA will provide a
mostly dry second half of the weekend. Still a slim chance of a
shower/storm in southern PA as the core of the high pressure
system will be positioned farther north with lingering moisture
along the Maryland border. Shortwave energy traversing PA would
be the forcing mechanism for any storms later today along the
Mason-Dixon line, although updraft/downdraft organization is
expected to be poor given deep layer shear on the order of 20
knots. Increasing sunshine through the day should help
temperatures warm into the low-mid 80s north and mid-upper 80s
in south central PA this afternoon.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH MONDAY NIGHT/...
The widespread stormy and unsettled pattern resumes Monday with
a shortwave trough and subsequent falling heights progressing
through the Great Lakes, putting the Commonwealth back in the
warm sector as deeper moisture is pulled north. Partly cloudy
skies to begin the day on Monday will allow for plenty of
destabilization. This combined with the above mentioned moisture
return and increasing deep layer shear of around 25-30 knots
will provide the ingredients for another round of strong storms
Monday afternoon/evening. Strong outflow winds and heavy
rainfall look to be the primary threats.

&&

.LONG TERM /TUESDAY THROUGH SATURDAY/...
Upper-level ridging early in the week will be replaced by
upper-level troughiness across the northeastern United States
for the second half of the week. By next weekend, the upper
level pattern will become more zonal.

As for sensible weather...a cold front will cross the area on
Tuesday, accompanied by a good chc of SHRA/TSRA. Behind this
front, a (slightly) cooler and drier airmass will return for
the remainder of the work week.

There could be a few aftn SHRA/TSRA on Thursday in response to a
weak shortwave trough. Otherwise, much of the second half of the
week (Wed-Fri) should be rain-free.

As sfc high pressure slides off the East Coast and winds become
southerly, warmer temperatures and increasing humidity will
return for next weekend.

&&

.AVIATION /07Z SUNDAY THROUGH THURSDAY/...
For the 06Z TAF package, not a lot of change from earlier
this evening.

Main issue overnight will be fog, given light winds and not
much in the way of clouds, other than some high cirrus clouds.
Still rather high dewpts the southern portion of central PA.

Showers now south of central PA, as of 1 AM.

Earlier discussion below.

Clearing skies and diminishing winds overnight should provide
good conditions for fog development. At 03z, we`re already
seeing hints of reduced vsbys and/or cigs at a few locations
around central PA (including IPT). I hit the fog/low clouds a
bit harder at some of the TAF sites than the model guidance is
suggesting, based on favorable meteorological conditions and
wet ground from earlier rainfall.

After any fog/low clouds mix out in the morning, expect dry
weather and widespread VFR conds for Sunday.

The next cold front will arrive early next week. Some of the
accompanying storms could be on the strong side once again.

Outlook...

Mon-Tue...SHRA/TSRA expected, with periods of fog and low
clouds overnight.

Wed...AM fog, then VFR.

Thu...Primarily VFR, although a few aftn SHRA/TSRA are
possible.

&&

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

&&

$$

SYNOPSIS...Guseman/Bowen
NEAR TERM...Guseman/Bowen
SHORT TERM...Guseman/Bowen
LONG TERM...Steinbugl/Evanego
AVIATION...Martin/Evanego