-- Discussion containing changed information from previous version are highlighted. --
354
FXUS61 KCTP 251624
AFDCTP

Area Forecast Discussion
National Weather Service State College PA
1224 PM EDT Tue Mar 25 2025

.SYNOPSIS...
-- Changed Discussion --
*Breezy conditions will accompany below normal temperatures
 through Thursday with clouds/snow showers expected Wednesday
*Late week warming/milder trend continues into the last weekend
 of March
*Periods of rain/showers are possible Friday into early next
 week within uncertain seasonal March-April transition pattern
-- End Changed Discussion --

&&

.NEAR TERM /THROUGH TONIGHT/...
-- Changed Discussion --
Cloudy skies evident along and north of US-6 this afternoon with
mostly sunny skies farther south. Mid level clouds should increase
across southern PA later this afternoon as shortwave energy
dives southeast from the Great Lakes and Ohio Valley. Clouds are
keeping temperatures stuck in the middle 30s across the northern
tier, while sunshine has allowed deep mixing and efficient
warming farther south where temperatures have made it into the
low 50s as of midday.

5-8kft mixing heights will continue to promote gusty winds from
the west peaking in the 25 to 35 mph range this afternoon. The
deep boundary layer/dry air mixing sounding profile will also
favor falling dewpoints with min RH in the 20-30% range across
the southern 2/3 of the CWA. The breezy conditions and low
humidity will contribute to an elevated risk of wildfire spread
this afternoon where a Special Weather Statement remains in
effect until 8PM. Fcst max temps 40-60F will be within +/- 5
degrees of climo and generally 5-10F cooler vs. yesterday
(largest 24hr maxTchange in the northern tier). Hires model data
indicates light precip should remain to the north and south of
the forecast area through 00Z/8pm.

Sfc wave passes well to the south of the PA line early tonight
and latest hires data indicates a very low probability of light
rain reaching the southern tier/MD line. Upper level trough
pivots into the area late tonight with rising probs for snow
showers downwind of Lake Erie into early Wednesday morning
thanks to an increasingly colder NW flow. Fcst lows range from
25-35F from NW to SE with some upside risk given a fairly steady
light NW breeze and lake stratocu spilling over the Allegheny
Plateau.
-- End Changed Discussion --

&&

.SHORT TERM /WEDNESDAY THROUGH THURSDAY NIGHT/...
-- Changed Discussion --
Wednesday will be the coldest day of the week with a brisk WNW
flow gusting 20-30 mph and max temps 5-10F below the historical
average for the end of March. We continued to edge dewpoints
lower and wind gusts a bit higher vs. NBM. MinRH is fcst to dip
into the 25-35% range across the southern 2/3 of the fcst area
which should maintain at least a slightly elevated risk of
wildfire spread (although tempered to some extent by the cooler
temps). Scattered lake/terrain enhanced convective snow showers
will be most likely north of I-80, though a few could make it
farther inland. Cold pocket at 850mb suggests increasing
cu/stratocu clouds into the afternoon coincident with the
diurnal cycle, perhaps all the way down to the I-81 corridor.
SNSQ parameter lights up across higher elevations of northern PA
on Wednesday, illustrating the potential for stronger convective
snow showers and brief reductions in visibility. High
temperatures in the low 40s all along the I-80 corridor should
mitigate the flash freeze potential and any need for snow squall
warnings, but a long-fused SPS alerting motorists of reduced
visibility in snow showers may be needed.

Surface ridging and an associated low-pwat airmass building
into PA should support clearing skies and cold temps Wed night
into AM Thursday. Min temps will be below climo and have some
downside risk Thursday morning - potentially falling into the
upper teens across parts of west central PA under the sfc ridge
axis/weakest pressure gradient.

A warming trend is fcst to begin on Thursday as the high shifts
off the NC coast. No precip is expected during the day with
highs projected to rebound +5-10F vs. Wednesday into the 45-55F
range or near average for late March. Things start to get
tricky Thursday night with an early Spring baroclinic zone
setting up over the region. The NAM and CMC (to a lesser extent)
are bullish vs. the other guidance in bringing a stripe of QPF
to the northern tier along a stalled frontal zone; temps over
this area appear cold enough for a rain/snow mix if this occurs.
Confidence is low at this point and the pattern uncertainty
grows heading into late week and the upcoming weekend.
-- End Changed Discussion --

&&

.LONG TERM /FRIDAY THROUGH MONDAY/...
All medium range guidance indicates the upper trough will be
replaced by a building ridge along the East Coast late this
week, supporting a trend toward warmer weather late week into
next weekend. However, there is plenty of uncertainty regarding
how far the dying cold front gets.

Some guidance indicates this boundary limps into Northern PA
Friday, then lifts north of the border for the weekend. In this
scenario, mostly sunny skies and 850mb temps of near 10C south
of the front could support widespread highs in the 70s. Other
guidance indicates the front stalls out south of PA next
weekend, resulting in a much cooler and potentially rainy
scenario, with an easterly flow off of the Atlantic and
potential overrunning ahead of approaching low pressure over the
Midwest. The current weekend forecast reflects a middle ground
compromise between these solutions in regards to temps and POPs.

There is broad model consensus that an upstream surface low will
track over or just north of PA Monday, supporting a good chance
or rain or rain showers.

&&

.AVIATION /16Z TUESDAY THROUGH SATURDAY/...
MVFR StratoCu deck has finally arrived at KBFD and it expected
to hang tough across the northern tier into late morning before
scattering out. Sunshine elsewhere and resulting increased
mixing should result in fairly gusty west winds Tuesday. Bukfit
soundings support frequent gusts to around 25kts from mid
morning until early evening.

An area of weak low pressure will likely pass south of PA
Tuesday night. The bulk of current model guidance keeps any
precipitation or cig reductions from this system south of the PA
border.

Outlook...

Wed...Slight chance of AM snow showers/MVFR cigs NW Mtns.

Thu...No sig wx expected.

Fri...PM rain/low cigs possible, mainly N Mtns.

Sat...Rain/low cigs possible, mainly N Mtns.

&&

.CLIMATE...
Tracking 3rd driest year-to-date at Harrisburg with with total
precipitation of 4.69" through March 24th. No precipitation is
forecast through Thursday and chances remain low into the
weekend.

&&

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

&&

$$

SYNOPSIS...Steinbugl/Banghoff
NEAR TERM...Steinbugl/Banghoff
SHORT TERM...Steinbugl/Banghoff
LONG TERM...Fitzgerald
AVIATION...Fitzgerald/Gartner
CLIMATE...Steinbugl