545
FXUS61 KCTP 051357
AFDCTP

Area Forecast Discussion
National Weather Service State College PA
957 AM EDT Sun May 5 2024

.SYNOPSIS...
-Rain tapers to showers and a few thunderstorms to close out
 the first weekend of May
-Warmer and drier on Monday; increasingly unsettled Tue-Fri
-Late week cooling trend continues through Mother`s Day weekend

&&

.NEAR TERM /THROUGH TONIGHT/...
No major changes to this morning`s forecast with 850mb jet
driving light/mdt rain from southwest to northeast across CPA.
Expect the steadier rain to shift to the east with time giving
way to a more showery regime for later today through tonight.
CAD pattern with a moist east southeast upslope flow and
ridgetop fog should reign supreme over the northeastern quadrant
of the CWA with highs stuck in the mid to upper 50s. Meanwhile,
it looks like the western and southwestern portions of the area
will break into the warm sector with cloud breaks allowing
temps to reach the 65-70F range. The warmer temps will fuel
enough CAPE to mention a t-storm mainly along/west of US219 with
a MRGL SWO (1/5) from the SPC still clipping Warren County.

Rather mild tonight as a weak cold front presses southeast from
Lake Erie. Some lingering showers are possible especially near
the front. Guidance remains bullish on low clouds and fog
development overnight which may become locally dense in spots
into early Monday morning. Fcst lows are +10-15F above climo for
early May in the low 50s to near 60F.

&&

.SHORT TERM /MONDAY THROUGH MONDAY NIGHT/...
A.M. low clouds and fog should give way to some sun by Monday
afternoon especially across the northern half of CPA as high
pressure over the eastern Great Lakes directs drier/lower pwat
air into the region. Following a rather cool and damp weekend,
temperatures are forecast to trend much warmer with fcst maxes
getting back into the 70-80F range. The aforementioned frontal
boundary settling near the MD line will maintain a low chance
of showers/t-storms over the southern tier into Monday night.
Expect some fog again Monday night with lows ranging from the
mid 40s along the NY border to around 60F in the southern tier.

&&

.LONG TERM /TUESDAY THROUGH SATURDAY/...
Upper level ridging over PA indicates warm and generally dry
conditions are likely Tuesday. However, a warm front lifting out
of the Ohio Valley could result in increasing clouds with a PM
shower/tsra, primarily across the western counties. The bulk of
medium range guidance supports a very warm Wednesday with
scattered convection, as the area briefly breaks into the warm
sector south of a weak low tracking across upstate NY. A round
of convection may accompany the trailing cold front. Ensemble
mean pre-frontal 850mb temps around 16C suggests max temps as
high as the mid to upper 80s are possible over the Lower Susq
Valley.

The best chance for widespread showers and thunderstorms
appears to be on Thursday associated with a deepening upstream
trough and wave of low pressure riding along the stalled cold
front just south of PA. The surface low and deepest moisture is
progged to shift east of the area by Thursday night. However,
falling heights ahead of the upper trough will likely support
scattered, diurnally-driven convection Friday and Saturday,
along with a downward trend in temperatures. EPS mean 850mb
temps by Saturday are only around 3C, which is supportive of
highs ranging from just the mid 50s to mid 60s.

&&

.AVIATION /14Z SUNDAY THROUGH THURSDAY/...
Little improvement in flying conditions is expected over most
of Central PA today, as a moist southeast flow off of the
Atlantic persists. However, model soundings indicate some modest
improvement is possible late in the day along and west of the
spine of the Alleghenies, prior to the development of scattered
convection during the evening hours. The highest chance for TSRA
is at JST and BFD, mainly between 22z Sun and 03z Mon.

Areas of fog are likely Sunday night into early Monday as drier
air works in aloft, but ample moisture remains trapped at the
sfc beneath a thermal inversion. LIFR is possible at all
TAF sites late tonight. Most if not all airfields will trend
to MVFR or better by Mon afternoon after any early fog
dissipates. The highest chance for VFR conds Mon afternoon will
be north and west of a line from AOO to UNV to IPT.

Outlook...

Mon...AM low cigs/fog likely. Stray shower late.

Tue...Patchy AM valley fog possible, mainly Southern PA. Isold
PM tsra impacts possible Western PA.

Wed...AM low cigs possible NW Mtns.

Thu...Rain/low cigs possible. PM tsra impacts possible
southwest PA.

&&

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

&&

$$

SYNOPSIS...Steinbugl
NEAR TERM...Steinbugl/Bowen
SHORT TERM...Steinbugl
LONG TERM...Fitzgerald/Bauco
AVIATION...Fitzgerald/Colbert