Area Forecast Discussion
National Weather Service State College PA
715 AM EDT Fri Apr 3 2026
.WHAT HAS CHANGED...
* Certainty in a non-diurnal temp trend on Sunday is high.
* Slowed the heating/mixing in the E/NE zones by a few hours
today as cold air damming does not usually give up easily.
* Added mentions of gusty winds/small hail to the thunderstorms
on Sat.
&&
.KEY MESSAGES...
1) The cold air dam breaks today. Weak forcing touches off a few
rounds of showers and thunderstorms.
2) Temperatures near record levels on Saturday, mainly in the
south, ahead of a strong cold front which will pass through on
Easter morning.
3) Colder next week but warming up again by week`s end.
&&
.DISCUSSION...
KEY MESSAGE 1: The cold air dam breaks today. Weak forcing
touches off a few rounds of showers and thunderstorms.
Deep easterly flow continues to keep the eastern half of the
area in the cold wedge. Temps haven`t moved much overnight in
the eastern and central zones. They will likely struggle to rise
as fast as guidance has them doing thanks to the pesky cloud
cover. The clouds will take many hours to burn away in the
Poconos and northeastern mountains. But, the mixing will help
temps get very warm in the afternoon, especially in the west and
south. Showers over the NW this morning will creep a little to
the east, but dwindle as they do so. Thanks, stability. There
will be a slight nudge from some additional, but shearing,
forcing. That is currently generating storms over IL/IN. That
will be the kicker to help the well-mixed atmosphere this
afternoon and early evening to reach it`s full but limited
potential. The weak forcing will be timed right with peak
heating. The topography gives a helping hand to convective
initiation, and warm temps and almost-60F dewpoints supply
fuel. Mixed-layer CAPEs get in the 500-1000 J/kg range over the
west. But, the deep-layer shear will be decreasing at the same
time. So some storms could get tall, and generate some gusty
winds. This is most possible in the Laurels where it all come
together. Still, it`s only worth a MRGL risk of severe storms
today.
--------------------------------------
KEY MESSAGE 2: Temperatures near record levels on Saturday,
mainly in the south, ahead of a strong cold front which will
pass through on Easter morning.
A weak trough/front over the area tonight will move northward
and allow much warmer air in for Saturday. If we set record
maxes, they would more likely occur Sat than Fri. Maxes in the
70s N and 80-85F S. Clouds in the morning will mix away before
popping up in another life in the afternoon heating. Shear of
30KTs or so in the north and 20 in the south, but CAPE progged
in the S will beat that up north. Overall, the numbers only
yield a(nother) SPC MRGL risk day, but it covers all of Central
PA for Day2 (Sat).
The warm air will linger into the nighttime. But, by Sunday
morning, a strong cold front will be crossing the CWA from NW-
SE. The precip along the front will still have some
instability, so we left mentions of thunder in there. Temps on
Easter Sunday will be headed downward, losing 6-8F through the
whole day. Not a terrible rate, especially when it starts out
very mild (in the SE half). The band of rain/showers along the
front should be off to the SE of the CWA in the afternoon. Hold
onto your bonnets, as there will be some gusts into the 20s as
the cold air moves in. Lows Sunday night U20s N, U30s S.
---------------------------------------
KEY MESSAGE 3: Colder next week but warming up again by week`s
end.
From a precipitation perspective, scattered rain and/or snow
showers are possible Monday and Tuesday. A trough crossing the
Great Lakes will slide across PA during the Monday-Tuesday time
frame and should generate some SHSN. Temps will only be
favorable for an accumulation during the overnight periods.
Tuesday will be the coldest day with maxes not out of the 30s in
the nrn tier counties and only near 50F in the far S. Wednesday
morning will be the coldest under high pressure with mins below
freezing everywhere. This will occur about 3 days before the
climatological average date of the last freeze, so we`ll be
right on track. Thursday morning could be that cold, too, but
that depends on just how fast the high slides to the east. For
now, we`ll hang with the NBM/WPC guidance mins then (30s). The
outlook trends warmer for the end of work week with some showers
in the north.
&&
.AVIATION /12Z FRIDAY THROUGH TUESDAY/...
Flight categories will improve west to east between 12-18Z
Friday as cold air damming erodes, with high confidence (>80%)
of VFR prevailing across most of our airfields after 18Z.
Confidence of VFR is more moderate (50-60%) at KBFD, where
convective activity and higher moisture could limit cloud
ceiling heights to MVFR.
Scattered convection is expected to develop
across north-central and western PA after 18Z, driven by peak
diurnal heating and increasing instability. Showers with a few
thunderstorms are possible, especially near KBFD where SBCAPE of
500-1000 J/kg and steeper 0-3km lapse rates will be in place,
though scattered thunderstorms will also be possible at KIPT and
KUNV later in the day as convection advances eastward. Given
the scattered, loosely organized nature of this convection,
PROB30s have been used at these sites to signal at the
thunderstorm potential, though timing and coverage will be
determined with later TAF packages.
From 00Z Saturday to the end of the TAF package, flight
categories are moderately likely (50% confidence) to
deteriorate to at least MVFR across our airfields as wind
diminishes overnight with the mild, moist air mass in place.
The highest confidence in flight restrictions is across the
Northern Tier (KBFD), with IFR likely (60-70%) by 06Z. Moreover,
lighter cloud cover across the Lower Susquehanna Valley (KMDT,
KLNS) could contribute to low stratus and fog development, with
the LAMP showing a low to moderate (30-40%) chance for at least
IFR visibilities between 09Z and 12Z.
Outlook...
Sat...Restrictions possible in the morning due to light winds
and low-level moisture, with VFR in the afternoon outside of
scattered showers and thunderstorms..
Sun...Restrictions possible with showers and thunderstorms
ahead of a strong cold front.
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.
&&
.CLIMATE...
Daily record max temperatures for April 3rd and 4th:
SITE APRIL 3 APRIL 4
Harrisburg 86/1963 | 82/1999
Williamsport 83/1963 | 84/1921
Altoona 81/1963 | 80/1950
Bradford 80/2010 | 72/1981
State College 79/1963 | 81/1910
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
Dense Fog Advisory until 11 AM EDT this morning for PAZ058.
&&
$$
WHAT HAS CHANGED...Dangelo
KEY MESSAGES...Dangelo
DISCUSSION...Dangelo
AVIATION...Teare
CLIMATE...Steinbugl
