Area Forecast Discussion
Issued by NWS State College, PA

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FXUS61 KCTP 222351

Area Forecast Discussion
National Weather Service State College PA
751 PM EDT Fri Sep 22 2017

A ridge of high pressure at the surface and aloft will stay
anchored across the Lower Great Lakes, Ohio Valley and
Northeastern States through at least the middle of next week.
This will continue dry and unseasonably warm weather in


Another summer-like evening here in the first few days of
autumn. Temps running at least 5 to 10 degrees above normal
under mostly clear skies. Upper ridge entrenched with fair
weather persisting tonight. Fog will form once again in the
valleys, making very similar conditions to the past few
mornings. Mins could run a degree or two milder in the NW since
some mid level clouds could come in from the north. Conversely,
lower mins possible tonight vs Fri AM in the SE with comparably
fewer clouds there.


Dry and warm with comfortable humidity. 8H temps change little,
but inversion lowers even a bit more. Scattered mid clouds may
also keep temps down a deg or two vs Fri aftn, but persistence
is a strong companion in this kind of pattern.


It looks to remain dry into at least Wednesday as the ridge
that kept Jose locked offshore protects us for several more
days. Weak flow at night should allow for valley fog to form and
to greet morning commuters.

At this time it looks like the remnants of Jose will remain
offshore with the next chance for rain locally being with a
weakening cold front that the latest guidance brings our way late
Wednesday into Thursday.

The models agree in keeping the upper ridge the dominant feature
into midweek, before northern stream energy starts to chew away
at our high heights. The ECMWF is faster in bringing a shortwave
through the NERN US while the GFS is slower but carves out an
intense upper low dropping into the OH Valley for next weekend.
This feature is not in the GEFS nor is it in the ECENS so a
flatter faster moving shortwave seem the better idea. Either
way it will lead to a cool down by the end of the week into next

NHC models keep Maria well east off the coast as it heads north
later next week. The ECENS shows the closest approach to the
eastern seaboard, bringing the storm about 100 miles east of
Cape Hatteras around Thursday. It will give us something to
watch over the next week or so. It`s worth noting, this storm
will be moving over waters that have been churned up by Jose.
While still a large and dangerous storm, between the shear and
colder waters, it has seen its best days intensity-wise.


High pressure will remain over Pennsylvania through Saturday,
ensuring VFR conditions and light wind for most of the area. The
only issue will be some patchy valley fog during the early
morning hours. The air mass is a bit drier than yesterday, so
expect fog to be confined to the deep river valleys north of
I-80, likely leaving the central Pa airfields unaffected. Can`t
rule out a brief reduction at KBFD or KIPT around dawn, but
believe the odds are a bit below 50 pct based on a combination
of conditional climatology, SREF prob charts and MOS guidance.


Sun-Wed...Patchy AM valley fog possible, mainly northern Pa.


Astronomical Fall/Autumnal Equinox begins at 4:02 PM this




SHORT TERM...Dangelo
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