Lancaster, Pennsylvania 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

397
FXUS61 KCTP 051557
AFDCTP

Area Forecast Discussion
National Weather Service State College PA
1157 AM EDT Sun Apr 5 2026

.WHAT HAS CHANGED...
* Continue to advertise more snow vs rain to the north of I-80
  Monday/Monday night in association with a clipper system
  dropping SE from the Great Lakes.
* Increased sky cover to near 100 percent today and tonight
  across the Laurels and NW Mtns with a transition to decent
  breaks east of the I-90 corridor later this afternoon/early
  tonight.

&&

.KEY MESSAGES...
1) Cold front pushing east of the Susq Valley with rain ending
early this afternoon.

2) Light snow likely across the northern tier Monday/Monday
night.

3) Much colder next week but warming up again at week`s end.

&&

.DISCUSSION...
KEY MESSAGE 1: Cold front pushing east of the Susq Valley with
rain ending early this afternoon.

An approximate 4-6 hour period of light to briefly moderate
rain fell along and just in the wake of a cold front this
morning as a deep layer of uvvel accompanied the well-defined,
thermally direct circulation linked to the right entrance region
of a southwesterly upper level jet.

As the rain ends in the Scent Mtns and from the Susq Valley East
early this afternoon, sct SHRA will return to the NW mtns as the
primary mid/upper level trough moves east from Mich and Ohio.

As the temps in the clouds and at the sfc get colder, the precip
will become frozen and have little time/altitude above freezing
to melt on it`s way to the ground. There could also be a little
graupel in a shower or two if they can tap a little CAPE. These
SHSN will last into the first half of the night. Just a dusting
of an accumulation is expected, mainly along and N of Route 6.

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

KEY MESSAGE 2: Light snow likely across the northern tier
Monday/Monday night.

A Clipper-like system dives down from Central Canada and across
the Great Lakes on Monday. It has meager moisture to drop on
Central PA, but numerous SHSN expected in the northern tier.
More sparse showers (mixed) will make it south of I-80. Sfc
temps are expected to get into the 40-45F range in the nrn tier
in the aftn on Mon, so the p-type may be a mix, too. The NAM
does paint some meager CAPE in the NW, too. So, there could be a
briefly heavier spot of precip/snow here and there. At this
point, it doesn`t look dynamic enough to make serious snow
squalls. However, the forcing looks strongest later in the day
and evening Monday as a short wave trough passes overhead. A
couple of models show the SHSN dipping into the Laurels in the
evening. The SHSN will linger all night and perhaps into Tuesday
AM until the (broad) axis of the upper trough moves past the
CWA. Overall, the accums could be an inch or so in the nrn tier
and perhaps a dusting in the Laurels and Alleghenies. Wouldn`t
be surprised to see a dusting on the ridge tops around Happy
Vally by Tuesday AM.

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

KEY MESSAGE 3: Much colder next week but warming up again at
week`s end.

Tuesday MA mins will be cold enough for frost over all of the
area, but wind of 10-15 G 20-25KT will keep that from happening.
The cold pool will be deepest on Tuesday, limiting max temps to
the freezing mark near the NY border and 45-50F in the srn
cities. These numbers will be about 10-12F below normals.

Wednesday morning will be the coldest this week due to the
center of the sfc high being right overhead. Morning mins will
be well below freezing everywhere. Even the Lower Susq will get
into the L-M20s. The start of the growing season (date of the
normal last spring freeze) is not until the 11th there. So, we
probably won`t be issuing frost/freeze products for that
morning. But, collaboration with our neighboring WFOs will weigh
heavily on that decision.

It then warms up close to normals maxes on Wed as the sfc high
slides to our E and S and the wind turns to come out of the S
and we should be sunny. Thursday looks much warmer, jumping
another 10-15F over Wed`s numbers. PoPs stay pretty low as we
warm up as the sfc high noses back into the Deep South. That
will help to keep moisture from the Gulf from getting to us.

&&

.AVIATION /15Z SUNDAY THROUGH THURSDAY/...
Flight categories and LLWS will improve from west to east across
the Central Ridge and Valley region of PA through this afternoon
in the wake of a cold front.

MVFR ceilings are moderately likely (50-60%) to persist into the
mid afternoon 19-20Z at KUNV and KAOO as colder drier air works
in, while mainly VFR CIGS are expected to persist at the tail
end of an area of rain and afterward across the Susq Valley.

Conversely, deepening cold air and the approach of an upper
level trough will combine with orographic lift to increase the
chc for SHRASN this afternoon and evening at KBFD and KJST with
IFR to MVFR CIGS.

MVFR to briefly IFR CIGS will occur tonight into Monday at KBFD
and KJST with ocnl -shsn. Variable MVFR to low end VFR bkn cigs
will continue tonight acrs the Central Mtns with VFR at the
Susq Valley Airfields.

Wind gusts from 270-290 deg later today and tonight could exceed
30 KTs at times, as the colder air pushes in beneath the
subsiding (left rear) portion of an upper level jet max.

Outlook...

Mon...Breezy and cooler with MVFR N/W and VFR elsewhere, with
scattered rain/snow showers possible.

Tue...Mainly VFR with a few rain/show showers.

Wed-Thu...VFR.

&&

.CLIMATE...
Record high temperatures were set at the following locations on
April 4th:

Harrisburg set a record high temperature of 83 degrees,
breaking the old record of 82 degrees set in 1999. A continuous
weather record has been kept in Harrisburg since 1888.

Bradford set a record high temperature of 77 degrees, breaking
the previous record of 72 degrees set in 1981.

Altoona tied a record high of 80 degrees, where the previous
record was set in 1950.

&&

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

&&

$$

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