Harrisburg, Pennsylvania 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

191
FXUS61 KCTP 261636
AFDCTP

Area Forecast Discussion
National Weather Service State College PA
1236 PM EDT Thu Mar 26 2026

.WHAT HAS CHANGED...
* Did add a mention of localized severe storms with strong winds
  late this afternoon and early evening, mainly for northwest
  and north-central PA.

&&

.KEY MESSAGES...
1) Noticeable warmup this afternoon will precede rain and
thunderstorms this evening, followed by a chilly/raw cool down
for the end of the week into the last weekend of March.

&&

.DISCUSSION...
KEY MESSAGE 1: Noticeable warmup this afternoon will precede rain and
thunderstorms this evening, followed by a chilly/raw cool down
for the end of the week into the last weekend of March.

Strong warm and moist advection is well underway
this afternoon across the Commonwealth, with temperatures
climbing into/through the 70s in many locations. With surface
dew points also on the rise (should reach the 50s by late
afternoon, at least across northwest PA), we will destabilize
the environment, to the tune of 300-600 j/kg of MLCAPE by later
in the day. Shear profiles will also be strengthening, as
925-700 mb flow increases markedly into the early evening.

Buoyancy and shear profiles alluded to above will create an
environment supportive of at least isolated severe thunderstorms
from roughly 4-9 pm, as a strong cold front pushes from north-
south across the state. Damaging wind gusts will be the primary
threat, with areas north of US-22/I-78 having the most risk.

One good thing with this system is the probability of 0.5-0.75"
rainfall, with locally higher amounts possible, particularly
across the Alleghenies. Given long-term dryness in many parts of
the state, such rainfall is certainly welcome.

Later tonight and early Friday, the front should make its way
south of the Mason-Dixon line, with strong low-level cold
advection ensuing. As a result, Friday will be a much chillier
day, with afternoon high temperatures a good 25-35 degrees lower
than on Thursday, along with a stiff N-NW breeze.

For much of the weekend, uneventful weather is foreseen, as a
large surface high pressure system builds into the eastern
states to bring dry weather. Temperatures will start out chilly
on Saturday, with daytime highs only in the 30s and 40s across
central PA. Sunday will begin a moderating trend, once the
aforementioned high pressure system pushes off the east coast,
and winds shift into the S and SW.

&&

.AVIATION /16Z THURSDAY THROUGH MONDAY/...
VFR conditions will prevail beneath a shield of mid and high
clouds, based AOA 8000 FT AGL, that will continue to stream SE
across PA today.

The main concern in the near-term (through 14Z) will be LLWS
concerns with the axis of a 40-45kt swrly 850mb LLJ shifting
slowly east across the region during the early to mid morning
hours today.

The potential for sub-VFR conditions will begin at BFD this
afternoon. Conditions there will steadily deteriorate to IFR
later this afternoon and stay mainly IFR to LIFR into tonight.

A cold front will gradually approach the area and is expected
to be stationed east-to-west just north of the PA-NY border
around 00Z Friday. Another period of LLWS will occur late today
through the first half of tonight as a second WSW LLJ moves over
Central PA ahead of the cold front.

Showers and scattered storms will be focused along the front;
however, recent hi-res model guidance does indicate some storms
ahead of the front and have outlined these in PROB30s at BFD
given slightly higher confidence.

Further south, SHRA will be introduced in the TAFS prior to 00Z
Friday at IPT/JST prior while model guidance suggests that this
precip will begin at UNV/AOO in the 00Z-01Z Friday timeframe.

Further SE (MDT/LNS) showers will reach the region around 02-03Z
Friday.

Outlook...

Fri...-SHRA become more widespread with a slight chance of
TSRA. Restrictions likely.

Sat-Sun...VFR.

Mon...SCT -SHRA with restrictions possible

&&

.CLIMATE...
Record high temperatures for March 26th:

Harrisburg      80 in 1921
Williamsport    78 in 1939
Altoona         79 in 1998
Bradford        73 in 2007
State College   76 in 1949

&&

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

&&

$$

WHAT HAS CHANGED...Jurewicz
KEY MESSAGES...Jurewicz
DISCUSSION...Jurewicz
AVIATION...Lambert
CLIMATE...Steinbugl