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-- Discussion containing changed information from previous version are highlighted. --
709
FXUS61 KCTP 270558
AFDCTP

Area Forecast Discussion
National Weather Service State College PA
158 AM EDT Tue Sep 27 2016

.SYNOPSIS...
-- Changed Discussion --
Showers will exit southeast PA early this morning with continued
clearing from west to east behind cold front. Today should
eventually turn out to be mostly sunny and pleasant. An upper
level low will drop south from the Great Lakes through the Ohio
Valley and cut-off over the Central Appalachians bringing periods
of showers from Wednesday into the weekend.
-- End Changed Discussion --

&&

.NEAR TERM /THROUGH TONIGHT/...
-- Changed Discussion --
Showers associated with cold front should exit the Lower Susq.
Valley by 09-10z per latest HRRR. Clearing is expected to push
east through the morning as well-defined dry slot/below normal PW
air overspreads the area behind departing cold front and upper
level low dropping south through the Great Lakes. There should be
enough gradient wind and dry air advection to limit fog formation,
duration and coverage. Overall expect improving conditions this
morning with a pleasant afternoon in store with max temperatures
within a degree or two of late September climate normals. Most
likely the best day this week. The model guidance is in good
agreement in taking the upper low southward to a position near
the southern tip of Lake Michigan by the end of the period/12z
Wed. Still not expecting any rain tonight but the trend in precip
chances will reverse and start to edge higher into midweek.
-- End Changed Discussion --

&&

.SHORT TERM /WEDNESDAY THROUGH WEDNESDAY NIGHT/...
-- Changed Discussion --
Big change in the weather pattern will set up with a long wave
trough and a cut off low dropping down over the Eastern U.S. and
several days with rain in the forecast. By Wed afternoon the
upper low is over Ohio and moisture is being pulled back north
along the Eastern Coast into PA.
-- End Changed Discussion --

&&

.LONG TERM /THURSDAY THROUGH MONDAY/...
-- Changed Discussion --
Chances for rain showers will increase Wed afternoon with periods
of rain showers likely Wed night into Thurs night as the low
continues south into Western VA.Friday the low begins to shift
back to the northwest continuing the wet pattern into Saturday.
Models hint that Central PA may be dry slotted for a bit friday
afternoon and night. Upper low begins to lift northeast Saturday
into Monday with gradually decreasing POPs. Lower Susq will be
driest over the weekend and dry Monday with increasing chances
farther north across the higher terrain of the northern tier where
chances will linger into Monday morning. Temperatures will be a
little milder at night but cooler during the day with clouds and
periods of showers thereby averaging around normal.
-- End Changed Discussion --

&&

.AVIATION /05Z TUESDAY THROUGH SATURDAY/...
South-southeasterly flow ahead of a cold front has brought
widespread MVFR with areas of IFR to the region. Expect continued
reduced conditions throughout the evening and into the overnight
before drier air begins moving in behind the cold front Tuesday
morning. Any improving conditions after midnight will probably
just set the stage for the development of fog so earlier confidence
in clearing is now not so high.

Tuesday will start with most areas still experiencing MVFR/IFR,
but drier air on a gusty NW breeze will lead to rapidly improving
conditions in the few hours just after sunrise.

Wed should be the last good VFR day before more showery and
cloudy conditions develop later in the week into the weekend with
widespread reduced conditions likely.

Outlook...

Wed...Showers/cig reductions possible late.

Thu-Sat...Sct showers/cig reductions possible, esp w mountains.

&&

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

&&

$$
SYNOPSIS...Steinbugl
NEAR TERM...Steinbugl
SHORT TERM...Grumm
LONG TERM...Watson
AVIATION...La Corte