National Weather Service Weather Forecast Office

• Home
• Site Map
• News
• Organization
• Search for: NWS All NOAA 

-- Discussion containing changed information from previous version are highlighted. --
000
FXUS61 KCTP 111916
AFDCTP

Area Forecast Discussion
National Weather Service State College PA
316 PM EDT Thu Apr 11 2024

.SYNOPSIS...
-- Changed Discussion --
-Periods of locally heavy rain moving quickly across the area
 this evening through tonight; southeast wind gusts up to 45 mph
-Remaining windy Friday-Saturday with gusts 40+ mph and showers
 ending by Saturday night; max/min temps cooling down by 10-15F
-Showers return on Sunday; temperatures trending above average
-- End Changed Discussion --

&&

.NEAR TERM /THROUGH TONIGHT/...
-- Changed Discussion --
Latest MRMS radar mosaic shows an uptick in showers moving
quickly to the north over the western half of the CWA this
afternoon. Expect shower activity to continue to ramp up
through this evening in conjunction with increasing large scale
forcing downstream of amplifying/phasing mid level trough over
the Mid-South, favorable upper jet dynamics, and anomalous
pwats (+1-1.5" or +2SD) driven northward into CPA behind
strengthening southerly 50+kt 850mb jet.

Initial concern is for a swath of locally heavy rain to set up
over the western half of the CWA between roughly 00-06Z. There
is a decent signal in the HREF to potentially exceed 1hr FFG.
The quick movement is a limiting factor, and the localized
nature of the risk will preclude watch issuance at this point.
However, the evening shift may be inclined to go with a very
short-fused FFW if confidence increases and +RA signal
manifests.

Second concern is the potential for localized strong to damaging
wind gusts. The convective environment will be characterized by
high shear and low CAPE, but given the magnitude of the low
level flow it`s conceivable that even with meager instability
that we could see an isolated wind gust of 50-60 mph. Time of
day is certainly a limiting factor. The HREF shows a slight
uptick in MUCAPE over the eastern portion of the CWA btwn 06-12Z.
SPC did expand the MRGL risk to cover the remainder of the CWA
through 12Z Friday.
-- End Changed Discussion --

&&

.SHORT TERM /FRIDAY THROUGH SUNDAY/...
-- Changed Discussion --
WINDY FRIDAY-SATURDAY: The deep upper level trough/closed low
carved out from the eastern Great Lakes into the southeast U.S.
on Friday will lift out over the weekend. Large scale forcing
associated with the upper low combined with the arrival of sub
zero air at 850mb, steepening lapse rates, and a blustery west
wind will result in considerable shower activity Friday into
early Saturday. Showers on Friday appear to be more instability
driven, while lingering showers early Saturday are more
orographically enhanced. Temps look cold enough for rain/snow
mix over the NW mtns Friday night-AM Saturday with a coating
possible on non paved surfaces.

Strong to near advisory level wind gusts (35-45mph) are
forecast Friday into Saturday as pressure rises quickly increase
in the wake of the cold frontal passage (Friday morning) and
colder air arriving aloft ramps low level lapse rates and
enhanced boundary layer mixing. A wind advisory may be needed.
Gusty winds should gradually fade by Saturday night along with
lingering showers over the Allegheny Plateau.

Conditions dry out Saturday night into early Sunday before POPs
ramp up again from northwest to southeast ahead of a cold front
pushing Southeast from the Great Lakes Sunday
afternoon/evening.

After a noticeably cool down Fri-Sat with gusty winds, expect a
nice warm up to end the weekend with highs rebounding +10-15F
into the 60-75F range.
-- End Changed Discussion --

&&

.LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/...
-- Changed Discussion --
Latest EPS/GEFS support much milder weather to end the weekend,
as the upper trough lifts out and most of Central PA breaks
into the warm sector south of a weak wave of low pressure
passing north of the state. A round of showers could accompany
the trailing cold front Sunday PM, then an additional round of
showers is possible Tue/Wed associated with the stalled boundary
returning north as a warm front. Current ensemble plumes
indicate any rainfall should be relatively light Sun PM-Wed, so
no additional flooding concerns.

Ensembles currently support above average temps Sunday into
the middle of next week. EPS mean 850mb temps surge to around
12C by Tue/Wed, sufficient for highs in the 75-80F range given
enough sun.
-- End Changed Discussion --

&&

.AVIATION /19Z THURSDAY THROUGH TUESDAY/...
-- Changed Discussion --
Currently IFR (NW) to VFR (SE) with deterioration of conds
across southern PA later this morning into the afternoon. A
brief spell of dry conds will occur this morning, allowing for
some improvement before widespread deterioration later this
afternoon as SHRA moves into the area from the west. Recent
guidance has pulled all airfields across central PA down to IFR
thresholds later this afternoon into the evening, with fairly
good agreement. Thunderstorms are possible across much of the
area from 22Z Thu-06Z Fri and have outlined the best timing with
VCTS groups, although timing will need fine tuned in future
packages.

The concern for LLWS will also be on the increase after 22Z Thu
and into the end of the TAF period. A south-southeasterly LLJ
will strengthen over central PA through the day Thursday and
become strongest from 23z Thu - 06z Fri. Given the presence of
sfc gusts in the 20-30 kt range during the daylight hours, the
highest chance for strongest LLWS will be between 00z and 06z
Fri with probabilities becoming lower after 08Z.

Outlook...

Fri...Numerous showers with sub-VFR conds likely and a gusty
west wind.

Sat...Scattered showers with sub-VFR possible over the western
airfields (KBFD and KJST). A gusty west wind continues.

Sun...Mainly VFR, but a chance of late day showers and brief
restrictions.

Mon...A few lingering showers across the west.
-- End Changed Discussion --

&&

.CTP WATCHES/WARNINGS/ADVISORIES...
Wind Advisory until 11 PM EDT this evening for PAZ024-033.

&&

$$

SYNOPSIS...Steinbugl
NEAR TERM...Steinbugl
SHORT TERM...Steinbugl
LONG TERM...Fitzgerald/Bauco
AVIATION...Bauco/NPB