Tuesday, June 28, 2016, 6:16 PM EDT
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Area Forecast Discussion
Valid At
Tue, Jun 28, 3:32pm EDT
FXUS61 KCTP 281932
AFDCTP

Area Forecast Discussion
National Weather Service State College PA
332 PM EDT TUE JUN 28 2016

.SYNOPSIS...
A cold front will move slowly across central Pennsylvania and the
Susquehanna River Valley LATE this afternoon and this evening...
triggering the likelihood of showers and perhaps a few
thunderstorms containing gusty winds and hail. High pressure will
bring a period of mainly dry weather with comfortable humidity for
Wednesday and Thursday. Another cold frontal system will approach
for the end of the week.

&&

.NEAR TERM /UNTIL 6 AM WEDNESDAY MORNING/...
Surface cold front extended from just near KELM...ssw to KUNV and
KAOO at 1830Z, and was marching slowly to the east. Relatively
high cape but minimal deep layer shear was leading to scattered
thunderstorms that were slightly more organized than typicalpulse
storms.

A few of the storms were briefly strong enough to produce up to
dime dime hail...though WSR 88D hail estimates reflected the
potential for around 1 inch diameter hail.

the storms will soon be moving into an envir across the lower Susq
Valley that contains a little better instab and shear with DCAPES
around 1000 j/kg...which means and an increasing threat for
localized, damaging microbursts. 

The convection will linger into this evening and slowly weaken 
across the SE zones while a compact short wave near London
Ontario late this afternoon drops sewd and spreads increasing
strato cu clouds and isolated showers later tonight and early
Wednesday. cigs could dip below 1 kft agl across the nw mtns for
4-6 hours late tonight through the mid morning hours Wed. Skies
across much of the central ridge and valley region should turn
clear to partly cloudy with patchy valley fog possible after
midnight.

Min temps early Wednesday will range from around 50F across the nw
mtns...to the lower and mid 60s in the far SE where dewpoints
don't get below 60F and a little wind will likely trim the temp
fall there.

&&

.SHORT TERM /6 AM WEDNESDAY MORNING THROUGH WEDNESDAY NIGHT/...
Wednesday looks stellar for late June in most places across
central and southern PA. Afternoon high temps will be near normal
and a partly to mostly sunny sky after any morning low
clouds/patchy fog burn off.

Just a little wind from the NW (gusting into the mid teens)
with the 6mb gradient across the state. With respect to the
potential for any showers...700 mb temps dip near 0C are noted 
across the northern mtns during the afternoon hours with a fairly
distinct CFA near the axis of steepest mid level lapse rates of
6.5C/KM. Showers should be isolated with rainfall under one tenth
of an inch.

&&

.LONG TERM /THURSDAY THROUGH TUESDAY/...
The mean upper trough over the Northeastern CONUS loses amplitude
through the period, as a closed 500mb low dropping southward near
James Bay shifts eastward and a subtropical ridge off the Southeast
coast retrogrades slowly westward into the Gulf of Mexico. The
large scale pattern will have a decidedly summertime look to it
as we turn the calendar page to the month of July, with the main
belt of polar westerlies located along the U.S./Canadian border
and expansive upper ridge covering the southern 1/2 of the Lower
48. 

While much of central PA could use some rain, odds are that most
of the period will be a dry one. A frontal system moving through
the area on Friday will likely provide the only opportunity for
rain (scattered showers/T-storms) until the second half of next
week /beyond July 6th/. The upside to this will be a seasonably
warm and dry period expected to last through Independence Day
with seasonal temperatures and tolerable humidity.

&&

.AVIATION /19Z TUESDAY THROUGH SUNDAY/...
VFR expected at TAF sites across the western half of PA...while
scattered to numerous showers (and isolated to scattered TSRA)
will bring brief MVFR (and possibly very brief IFR) conditions to
areas near and to the east of a KIPT to KSEG and KTHV line.

The convection will slide east twd the Poconos early this
evening. After this evening...most of the week looks to be
dry...with mainly VFR conditions...as a drier airmass works into
the area.

OUTLOOK...

Wed...Early morning fog possible east. Isolated afternoon showers
possible mainly to the north of Interstate 80.

Thu...No sig wx expected.

Fri...Isold PM tsra impacts possible.

Sat and Sun...No sig wx expected.

&&

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

&&

$$
SYNOPSIS...Lambert
NEAR TERM...Lambert
SHORT TERM...Lambert
LONG TERM...Steinbugl
AVIATION...Lambert

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