Harrisburg, Pennsylvania 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

040
FXUS61 KCTP 062332
AFDCTP

Area Forecast Discussion
National Weather Service State College PA
632 PM EST Fri Mar 6 2026

.WHAT HAS CHANGED...
* Severe weather outlook area shifted a bit eastward for
  Saturday afternoon/evening; Slight risk now along and west of
  I-99 and Marginal risk extends across nearly the entire CWA

&&

.KEY MESSAGES...
1) Boom and gloom conditions precede the first severe
thunderstorm risk of 2026 on Saturday afternoon/evening

2) Significant Springtime warming Saturday through Wednesday
followed by seasonal moderation/cool down into mid-March

&&

.DISCUSSION...
KEY MESSAGE 1: Boom and gloom conditions precede the first
severe T-storm risk of 2026 on Saturday afternoon/evening

Clouds are slowly but surely thinning out east of I-99 and US-15
this afternoon, with plentiful sunshine and pleasant temperatures
farther west. The boom refers to temperatures soaring into the
mid 60s to low 70s across western PA where southwesterly flow
has eroded away at the cloud cover and given a glimpse of
spring. Meanwhile, low clouds, some patchy fog, and scattered
rain showers farther east are much more "gloom", with
temperatures stuck in the low to mid 40s. The 24-hr max temp
for Saturday will likely be reached shortly before 12AM Sunday
in the eastern zones.

The first severe T-storm risk for CPA in 2026 still on track for
Saturday afternoon and evening. The primary threat area and
greatest risk (level 2 out of 5) will be focused from the Upper
Ohio Valley into western PA with the eastern extent along the
I-99 corridor. The likelihood of increasing stability to the
east of the mtns will greatly reduce the severe storm risk
across the central and especially eastern portions of the fcst
area, though a Marginal Risk is in place there. A few morning
showers and storms will move across south central PA before more
substantial clearing builds in from the west. A linear
convective mode is favored with a potential line of strong to
severe storms capable of damaging winds tracking eastward from
Ohio into western PA late in the afternoon or evening.

The kinematic profile looks impressive for Pennsylvania
standards tomorrow, with steep mid-level lapse rates, elongated
right turning hodographs with 250-350 m2/s2 0-3km SRH, and 50kts
of deep-layer shear. The limiting factor, as usual, will be
thermodynamics thanks to the persistent cold wedge that will be
slow to erode tomorrow. A stronger surface inversion with
eastward extent means convection will tend to become elevated as
it moves into the eastern PA and that should limit the ability
for damaging winds to mix down the surface. Sufficient MLCAPE on
the order of 1000-1500J/kg along and west of the I-99/US-15
corridor will support the best chance for damaging winds (and
perhaps some hail or a tornado). The strength of storms as they
move east of I-99 will be dependent on time of day and degree of
clearing ahead of the line of storms. If storms are slower to
arrive and clearing occurs farther east than expected, the risk
of severe weather could expand.

KEY MESSAGE 2: Significant Springtime warming Sunday through
Wednesday followed by seasonal moderation/cool down into mid-
March

Cool wedge pattern finally breaks down and allows for a
significant springtime warming from Sunday into the middle of
next week. Frontal showers exit the area Sunday morning with
rain-free conditions likely holding into Tuesday. Dry and breezy
conditions on Monday could lead to the first elevated risk of
rapid wildfire spread for the year, especially across southeast
PA where less rain is expected over the next 36 hours.
Southwest flow builds by Tuesday, with a surge in temperatures
and dewpoints anticipated. April to May- like max/min temps
fcst +20-30 degrees above the historical average will challenge
daily records in some areas Tue/Wed. Cold frontal passage
Wed/Thu will bring some rain followed by a seasonable cool down
for late in the week into mid-March.

&&

.AVIATION /00Z SATURDAY THROUGH WEDNESDAY/...
As noted below, VFR conditions still across the far west as
of early this evening. Low CIGS and fog across the area to
the east already on the downward trend.

There could be a few showers, but mainly dry overnight.

For Saturday expect the far west to pick up a gusty southwest
wind at sites like JST and BFD.

Further east at UNV and AOO, CIGS will likely edge up some but
remain MVFR, while the visibilities come up.

The far eastern sites like IPT, MDT, and LNS will likely
remain MVFR and IFR all day, as cold air remains near the
ground.

The cold front is still a ways to the northwest at 00Z Sunday,
so used VCTS across the west at sites like JST and BFD, where a
storm could get into the area before 00Z and with the warmer
airmass. Storms a bit less likely and later at sites like AOO
and UNV.

Across the far east at sites like IPT, MDT, and LNS, the airmass
will be cooler and more stable, thus storms less likely. Also
the activity would be mainly later after 00Z.

Earlier discussion below.

Late afternoon update.

Adjusted TAFS for current obs and trends. Leading edge of the
clearing and milder air just east of a BFD, FIG, JST line.

More information below.

Low level wind shear will become a concern on Saturday as a
low level jet builds across northwest PA. Periods of rain are
possible in the morning before a more robust line of showers and
storms moves across the region in the afternoon and evening.
Visibility restrictions from storms should be relatively brief
(on the order of 20 to 40 minutes).

Outlook...

Sun...Trending towards VFR.

Mon...Restrictions possible as low-level moisture increases.

Tue...Restrictions possible in the morning due to low-level
moisture. Showers later in the day.

Wed...Restrictions likely in showers.

&&

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

&&

$$

WHAT HAS CHANGED...Steinbugl/Banghoff
KEY MESSAGES...Steinbugl/Banghoff
DISCUSSION...Steinbugl/Banghoff
AVIATION...Martin