Harrisburg, Pennsylvania 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

742
FXUS61 KCTP 131051
AFDCTP

Area Forecast Discussion
National Weather Service State College PA
651 AM EDT Fri Jun 13 2025

.SYNOPSIS...
* Trending mostly cloudy and humid with periods of showers and
  locally heavy downpours today through the upcoming Father`s
  Day weekend
* Unsettled pattern continues next week ample chances for rain

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
Surface cold front has drifted south to the Mason Dixon line
early this morning, and that`s where it`ll sit pat for the next
several days. The boundary aloft within the 925-850 mb layer
will reside over Central and Northern PA with pulses of enhanced
isentropic lift leading to periods of light to moderate rain
showers a isolated to scattered late afternoon and evening TSRA.

Light showers in east/west bands will gradually drift east and
expand in areal coverage as we progress through the day and
tonight as 60-65 KT jetlet drifts across the Ohio Valley and
aims its nose (and thermally indirect left exit region at the
CWA. Recent model runs picking up on this relatively compact
upper level feature prompted us to raise POPS quite
significantly in most areas tonight.

The rounds of rain today will likely be heaviest across the
SW part of the CWA where some moderate CAPE (Probability of
1000 J/KG equating to between 20-40 percent) will occur.

Any tstorms are fcst to remain non-severe with very low risk
of Flash Flooding through early tonight.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH SATURDAY NIGHT/...
The aforementioned cold front becomes wavy/quasi stationary
into Father`s Day weekend. An east to southeast low level flow
to the north of the front suggests the best instability will be
along the southwestern periphery of the CWA - and this area is
where the HREF indicates the best potential for diurnally driven
convection between 18-24Z.

Episodic showers and tstorms continue through Saturday with the
primary hazard being localized heavy downpours. WPC keeps most
of CPA in the MRGL ERO for D3/Saturday. It won`t be raining the
entire time/not a washout -- but most locations will see some
rain showers. Increased cloud cover along with humidity points
toward lower daytime highs (70s) and higher nighttime lows
(60s).

&&

.LONG TERM /SUNDAY THROUGH THURSDAY/...
Overall tone/message of the long term has not changed with this
late evening update = high PoPs (relatively for the long range).
While confidence in timing of the stronger waves is low,
confidence is high that we`ll get wet many of these days. WPC
ERO places PA in the MRGL category for Days 3,4,& 5 (Sat-Mon).

Prev...
Unsettled weather pattern continues into next week with ample
opportunities for rain. A series of shortwave impulses rippling
west to east into a high PW corridor within a quasi zonal or
"troughy" 500mb configuration from Midwest into the Mid
Atlantic/Northeast will continue to bring periods of rain
showers and locally heavy downpours. WPC ERO for Sunday (D4)
includes all of CPA while shifting the southern tier on Monday
(D5).

Sunday/Monday look like the coolest days with CAD signature
established to the north of sfc wave tracking through the
Delmarva. Temps rebound by midweek as flow shifts back to the
west/southwest.

&&

.AVIATION /12Z FRIDAY THROUGH TUESDAY/...
Morning fog at AOO will mix out by 14Z this morning, giving way
to VFR conditions at all airfields for most of the day. A few
showers or perhaps a thunderstorm are possible, especially at
JST and AOO, this afternoon, which could briefly reduce
visibility there.

Lowering ceilings and visibility will occur after 00Z tonight
with more widespread showers moving in. IFR or LIFR conditions
are likely at all airfields after 06Z and restrictions will
continue into Saturday.

Outlook...

Sat-Tue...Daily chances for showers and thunderstorms,
especially during the late afternoon and early evening hours.

&&

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

&&

$$

SYNOPSIS...Steinbugl
NEAR TERM...Dangelo/Steinbugl
SHORT TERM...Steinbugl
LONG TERM...Dangelo/Steinbugl
AVIATION...Banghoff