366
FXUS61 KCTP 251620
AFDCTP

Area Forecast Discussion
National Weather Service State College PA
1220 PM EDT Sat Jul 25 2026

.WHAT HAS CHANGED...
Minor changes changes to the cloud cover forecast for the rest
of the day.

&&

.KEY MESSAGES...
1) Pleasant/dry pattern with comfortably low daytime humidity
will last through today before humidity gradually climbs on
Sunday.

2) Turning more humid and unsettled early next week with the
highest probability for showers and thunderstorms Monday
afternoon and evening and again on Tuesday.

&&

.DISCUSSION...
KEY MESSAGE 1: Pleasant/dry pattern with comfortably low daytime
humidity will last through today before humidity gradually
climbs on Sunday.

Broad, low-level streamline convergence with its N/S axis near
the RT 219 corridor in Western PA was leading to an expanding
area of Strato Cu clouds based mainly between 3-4.5 kft agl. A
few light showers have also been observed in this area this
morning.

As upper level diffluence slightly increases from the west this
afternoon and a few embedded flat shortwaves move overhead,
there will be isolated to scattered showers with MU CAPE only
500 J/kg or less. Will leave the isolated afternoon TSRA in for
now to the west of RT 219, but would be surprised to see any in
that part of our CWA based on the amount of morning cloud cover
and TDs still only in the 50s to around 60F.

Surface convergence becomes more focused over the eastern half
of the forecast area for tomorrow. Slightly higher dew points
will allow for instability to be a little higher than it is
today, possibly approaching 1000 J/kg in a few locations. Though
upper level forcing looks to be weak, we would expect to see at
least a few showers and thunderstorms develop during the
afternoon.

KEY MESSAGE 2: Turning more humid and unsettled early next week
with the highest probability for showers and thunderstorms
Monday afternoon and evening and again on Tuesday.

Minor modifications for this period that will be highlighted by
a warm front moving across western PA Monday afternoon/evening,
followed by a rather potent/digging mid/upper level shortwave,
that will support a sub-995 mb sfc low over the Lower Glakes and
Western NY Tuesday afternoon and evening. Latest model runs have
trended several hours or so slower compared to runs 24 hours
ago.

The timing of the favorable lift associated with the thermally
indirect, left front quad of the 80+ KT jet max moving across
the Ohio Valley, WVA and southern PA Tuesday afternoon and
evening will help to enhance a low level lee trough and
convection along it. Scattered strong to severe TSRA are likely
Tue afternoon and evening over at least the eastern half of the
CWA with a second line of TSRA likely along the cold front
across NW PA Tuesday afternoon.

&&

.AVIATION /16Z SATURDAY THROUGH WEDNESDAY/...
Borderline MVFR-to-VFR conditions AT JST/AOO will likely
continue for the next couple of hours before VFR conditions are
more likely to prevail. Some scattered shower development is
expected this morning in close vicinity to JST/AOO; however,
confidence remains low in any showers impacting the airfield
through 18Z Saturday. Chances gradually expand northward and
eastward late this afternoon and evening, with increased chances
at BFD/JST in the 18Z-06Z timeframe for some showers but given
the scattered nature, not confident enough to include mentions
and/or restrictions at this time. If showers do form and go over
BFD/JST in this timeframe, MVFR ceilings appear to be the most
likely solution, generally between 2,000 and 3,000ft AGL for a
one-to-two hour period. Towards the end of the 12Z TAF package,
higher confidence in some restrictions at BFD/JST with lesser
chance at AOO/UNV based on recent HREF probabilities. Given this
trend, have highlighted MVFR-to-IFR restrictions which is
slightly more optimistic than GLAMP model guidance based on the
25th percentile member of the HREF ensemble. Lower solutions
can play out; however, especially if BFD/JST/AOO/UNV receive
any rainfall today which would promote lower restrictions based
on visibilities and ceilings between 08-12Z Sunday.

Outlook...

Sun...VFR favored with a few showers/storms possible, mainly
over western-central PA.

Mon-Wed...Restrictions likely in showers/storms.

&&

.CLIMATE...
Cooler than average temperatures across the region led to
multiple record low temperatures being broken for July 23rd and
July 24th across central Pennsylvania.

On July 23rd:

 * Altoona set a record low temperature of 47 degrees, breaking
   the previous record of 50 degrees set back in 1981.

 * Bradford tied a record low temperature of 38 degrees which
   was previously set in 1981.

 * Johnstown tied a record low temperature of 49 degrees which
   was previously set in 1983.

On July 24th:

 * Altoona set a record low temperature of 47 degrees, breaking
   the previous record of 50 degrees set back in 1957.

 * Bradford set a record low temperature of 41 degrees, breaking
   the previous record of 44 degrees set back in 1993.

&&

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

&&

$$

WHAT HAS CHANGED...Lambert/Bauco
KEY MESSAGES...Lambert/Bauco
DISCUSSION...Lambert/Bauco
AVIATION...Beaty
CLIMATE...Beaty