153
FXUS61 KCTP 051656
AFDCTP

Area Forecast Discussion
National Weather Service State College PA
1256 PM 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/...
The steadier rain has shifted into the northeastern tier of the
state. Showers are expected to develop this afternoon across the
western periphery of the CWA as time moves forward. The 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 and Somerset
Counties.

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 and
widespread 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 TUESDAY 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.

Upper level ridging over PA indicates warmer conditions are
likely Tuesday with highs reaching the upper 70s to near 80F.
However, a warm front lifting out of the Ohio Valley and a 500mb
short wave could result in increasing clouds with a PM
shower/tsra, primarily across the western counties.

&&

.LONG TERM /WEDNESDAY THROUGH SUNDAY/...
Unsettled weather will continue into the extended period.
Wednesday looks to be another warm day, with ensemble mean
850mb temps of 16C suggesting max temps well into the 80s
across the Lower Susq Valley.

The best chance for widespread showers and thunderstorms
continues to be focused on Thursday, with a deepening upstream
trough and sfc low pressure riding up the Ohio Valley and
across the area.

The surface low and deepest moisture is progged to shift east
of the area Thursday night. However, falling heights ahead of
the upper trough will likely support scattered diurnal
convection Friday and Saturday, along with a downward trend in
temperatures.

&&

.AVIATION /18Z SUNDAY THROUGH FRIDAY/...
IFR to low-end MVFR conds are expected to persist across most
of Central PA this afternoon, as a moist southeast flow off of
the Atlantic persists. However, some modest improvement is
possible this aftn along and west of the spine of the
Alleghenies, prior to the development of scattered convection.
The best chc for TSRA is at JST and possibly BFD, late this
aftn into this evening.

Areas of fog are likely overnight into Monday morning, with ample
low-level moisture and light winds beneath an inversion. LIFR
is possible at all TAF sites.

Most, if not all, airfields will trend to MVFR or better by Mon
afternoon once the AM fog/low clouds dissipate. The Lower Susq
Valley may actually be the latest to see improvement on Monday,
and there could be a few showers through the aftn.

Outlook...

Tue...Patchy AM valley fog possible. Isolated SHRA/TSRA possible
late across S/W PA.

Tues night-Wed...Isolated to scattered SHRA/TSRA possible, esp
N/W.

Thu...Rain/low cigs expected, with PM TSRA possible.

&&

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

&&

$$

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