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000
FXUS61 KCTP 231813
AFDCTP

Area Forecast Discussion
National Weather Service State College PA
213 PM EDT Fri Jun 23 2017

.SYNOPSIS...
The combination of an approaching frontal system and the
remnants of Tropical Storm Cindy will funnel a plume of deep
tropical moisture into the region today and tonight.
The cold front will push east across the region during the
morning or early afternoon hours Saturday, followed by drier and
cooler air with comfortable humidity that will last through
much of next week.

&&

.NEAR TERM /THROUGH TONIGHT/...
The first wave of rain is still falling on much of the Central
and Northern Mountains. RAP shows CAPEs nudging upward over
southern PA as the leading edge of the real soupy PWAT air
starts to surge into the NERN US. Analysis shows PWATs exceeding
2" (2-4 sigma) in a wide swath from the Louisiana Gulf Coast up
into eastern Ohio and western PA, and moisture transport
vectors are all pointing the plume right toward our CWA.

While much of the late morning into the mid afternoon will end
up with off and on showers over most of the region, by mid to
late afternoon a more substantial area of rain will
develop/advect into the area as the best moisture associated
with the remnants of Cindy, over far SERN Missouri at 12Z,
begins to affect the forecast area.

From earlier...

Kept temps close to Superblend/National Blend...ranging from
the low 70s over the northwest mountains, where overcast skies
are expected, to the mid 80s over the Lower Susq Valley, where
model RH profiles support partly sunny skies by afternoon.

&&

.SHORT TERM /SATURDAY/...
*Heavy rain and short-term flooding risk Friday-Friday night.

Local heavy rain threat will last into tonight, but confidence
not sufficient for a Watch at this time. Deep tropical moisture
(PW locally 2"+) associated with the remnants of TS Cindy will
combine with the approaching northern stream trough and cold
front to bring a slightly elevated risk of locally heavy
rainfall and potential flooding to portions of central PA.
Factors arguing against a Watch at this time are fairly narrow
window of heavy rainfall and general longer duration of 2"+
rainfall totals...occurring over a 12 hour plus timeframe.

If one area has a greater risk of minor flooding...it would be
the Laurel Highlands where a multi- model blend incorporating
HIRES models/CAMs remains fairly consistent with location of
max QPF. Enhanced terrain lift will also be a factor over a
region that has the lowest ambient short-term FFG in the CWA.

HWO continues to highlight lower end +RA/FF risk at this time -
later shifts should consider a FF watch at shorter ranges with
increasing confidence.

Heavy rain threat winds down late tonight as deepest
subtropical moisture is shunted east of the region after
midnight. Expect lingering moisture/rainfall associated with
the moisture remnants of TS Cindy to exit the area by Saturday
afternoon.

&&

.LONG TERM /SATURDAY NIGHT THROUGH THURSDAY/...
From a large scale perspective, the medium range forecast will
feature a seasonably strong/amplified upper trough settling over
the Northeast U.S into next week. The theme continues to be
above avg confidence in the pattern but low confidence in the
details.

Drier, low PW air arrives behind the cold front later Saturday with
decreasing clouds and lowering humidity providing a nice start
to the weekend. An extended period of comfortable, low-humidity
conditions with temperatures near to below late June climatology
are expected to last through the early part of next week. A few
cool nights early next week with min temps 40-55F.

Precipitation opportunities will be modulated by shortwave
impulses reflecting weak surface fronts/troughs which have low
predictability at this range. Any pcpn would be generally
scattered in nature and on the light side given below normal
moisture levels for late June. The 22/12z GEFS shows PW values
remaining below average through midweek which would tend to
favor mainly dry wx.

Temperatures should stay on the cooler side of climo through
midweek as the upper level trough shifts east of the area.
Differences continue with the trough evolution later in the
week with the GFS initially more amplified before building SE
U.S. ridge. The EC generally maintains a mean trough over the
Northeast CONUS into the second half of next week.

&&

.AVIATION /18Z FRIDAY THROUGH WEDNESDAY/...
-- Changed Discussion --
Widespread MVFR/IFR remains in place across central PA this
aftn, as the remnants of TS Cindy make their way across the
area. Showers are moving in from the west, some with locally
heavy downpours and sudden reductions in vsby. Thunderstorms
should develop as well, especially across srn PA where the sun
has come out. Storms may contain gusty winds.

Showers/storms will persist into this eve and tonight, with
localized downpours remaining likely. This will result in
significant reductions in both vsbys and cigs.

Gradual improvement to VFR is expected area-wide on Saturday,
as the system pulls east of the region.

.OUTLOOK...

Sat...Scattered restrictions in AM showers...otherwise
becoming VFR.

Sun...Mainly VFR.

Mon-Tue...Mainly VFR, but with a chance of SHRA/TSRA.

Tue...VFR.
-- End Changed Discussion --

&&

.EQUIPMENT...
KCCX radar will be offline for approximately 4 days starting
Saturday, June 24th for technicians to install the first of 4
major service-life extension upgrades. The work on the radar has
been scheduled to minimize potential impacts to operations and
will be delayed if hazardous weather is forecast.

&&

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

&&

$$
SYNOPSIS...La Corte
NEAR TERM...La Corte
SHORT TERM...La Corte
LONG TERM...Steinbugl
AVIATION...Evanego
EQUIPMENT...Lambert