Latest Area Forecast Discussion for Central PA

Here is the latest Area Forecast Discussion for Central PA

This text statement is the latest forecast reasoning from the NWS in State College, PA

See the links at the bottom of the page for previous issuances/versions of the statement as well as our other text statements.

912
FXUS61 KCTP 150924
AFDCTP

Area Forecast Discussion
National Weather Service State College PA
524 AM EDT Wed Apr 15 2026

.WHAT HAS CHANGED...
* Additional details on today`s thunderstorm threat

&&

.KEY MESSAGES...
1) Summerlike warmth visits the region this week with near-record
daily maxes and daily mins on tap for today and tomorrow.
Elevated risk of wildfire spread poss Thu.

2) Several periods of showers and thunderstorms expected during
the next few days, with the greatest amount of rainfall likely
occurring across northern and western PA. Some storms may be
severe, particularly across the northwest late this afternoon
and evening.

&&

.DISCUSSION...
KEY MESSAGE 1: Summerlike warmth visits the region this week
with near-record daily maxes and daily mins on tap for today and
tomorrow. Elevated risk of wildfire spread poss Thu.

A +2 sigma ridge over the Southeastern US will continue to drive
warm air up into the Mid Atlantic and Northeastern US. Temps as
of 09z in the 50s and low 60s are still sitting a degree or two
above the minT records at IPT and MDT. Record warmth will
remain possible through Friday morning.

Humidity has accompanied the heat thus far, with dewpoints in
the upper 50s and 60s expected again this afternoon. The flow on
Thursday will become more SWrly, with more large scale
downsloping off the Appalachians resulting in drier air at low
levels. RH values in south central PA may dip into the low 20s
pct Thu afternoon, which, combined with wind gusts over 20 mph,
may result in an elevated risk of wildfire spread, particularly
if that area remains rain free today/tonight.

We will say goodbye to the warmth for a while come Sunday after
a strong cold front knocks temps back to near the freezing mark
for the start of next week.

----------------------------------------------------------

KEY MESSAGE 2: Several periods of showers and thunderstorms
expected during the next few days, with the greatest amount of
rainfall likely occurring across northern and western PA. Some
storms may be severe, particularly across the northwest late
this afternoon and evening.

A decaying MCS moving from Lake Erie into NW PA has produced
wind gusts near 40 kts on the Erie lakeshore. As this system
moves east, multiple lines of convection may initiate early this
morning as waves in the top of the stable nocturnal boundary
layer lift parcels high enough to tap into a few hundred J/kg of
elevated instability. Sfc wind gusts will likely be less than
30 kts for most places given the stable sfc layer. This first
round of convection will be winding down by 10-11 AM, with a
lull in the action expected late morning into early afternoon.

This afternoon and evening, new convection is expected to
initiate along a west-east quasi stationary boundary and
remnant outflow boundaries. Cool temps at mid levels above very
warm and moist low levels will result in steep lapse rates with
SBCAPE progged above 1000J/kg across much of central PA. With
about 30-40 kts of 0-6 km bulk shear, discrete cells and
clusters/linear segments will be possible. Storm motions near 40
kts and DCAPE of 500-700 J/kg should be sufficient to produce a
respectable threat for damaging winds in the NW this evening.

There is also some potential for training convection later this
evening into tonight over NW PA as the mean flow becomes aligned
with WSW-ENE initiating boundaries and moisture continues to
advect in from the SW. Convection allowing models suggest there
could be a few stripes of 1-3" of rain across NW PA in areas of
repeated heavy rainfall. WPC continues a MRGL ERO for this
threat.

&&

.AVIATION /08Z WEDNESDAY THROUGH SUNDAY/...
A relative minimum in thunderstorm activity is expected through
the rest of the night, with only a few showers/isolated
thunderstorms showing up on radar as of 06Z. These should
largely stay away from any TAF sites, but may get close to UNV.
Light winds along with some breaks in the clouds has allowed for
locally dense fog to develop across parts of Central PA, and
IFR/LIFR conditions are expected at BFD and IPT for much of the
night. Confidence is low on visibility restrictions developing
anywhere else. LLWS is expected at JST, AOO, and possibly UNV
for the rest of the night with a 40 knot low-level jet overhead.

An ongoing MCS over Michigan will bring the next round of
thunderstorms to the region early this morning. These
thunderstorms will weaken as they approach the area, but will
enter northwest PA around 11Z. BFD and JST are most likely to
see showers and thunderstorms as this line moves through.
Conditions should improve to VFR through the morning behind this
line for all of Central PA with mainly dry conditions and
scattered mid and high clouds. West-southwesterly winds will be
sustained at 10 to 15 knots with gusts to 25 knots.

Another round of showers and thunderstorms is expected late this
afternoon and into the evening. These storms will be capable of
producing strong wind gusts, potentially in excess of 40 knots.
Northern and western TAF sites are most likely to see showers
and storms later today. Fog formation is possible as rain moves
out of the area Wednesday night, with BFD and IPT again being
the most likely to see fog.

Outlook...

Thu...VFR most of the time, but brief restrictions possible in
hit and miss showers and thunderstorms, mainly across the north
and west.

Fri...Restrictions possible early, then improving to VFR in the
afternoon.

Sat-Sun...Restrictions in SHRA possible.

&&

.CLIMATE...
Record high daily maxes and mins are possible this week as
summerlike warmth visits the region. Here`s a look at the
records as they stand right now, with a * indicating that the
forecast is equal to or greater than the record.

Record High Daily Max / Daily Min...

For Harrisburg:
April 15: 87* (1941) / 61* (2023)
April 16: 89 (2002) / 63* (1941)
April 17: 91 (2002) / 60* (2002)

For Williamsport:
April 15: 86 (1994) / 57* (2023)
April 16: 90 (2002) / 55* (2023)
April 17: 91 (2002) / 58* (1896)

&&

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

&&

$$

WHAT HAS CHANGED...Colbert
KEY MESSAGES...Banghoff/Colbert
DISCUSSION...Banghoff/Colbert
AVIATION...Bauco
CLIMATE...Colbert

Forecaster's
Discussion: