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fxus61 kctp 200132 

Area forecast discussion
National Weather Service State College PA
932 PM EDT Tue Sep 19 2017

a ridge of high pressure at the surface and aloft will stay
locked in place over Pennsylvania for the next 7 days. This
dominant weather feature will provide fair, warm and generally
dry weather throughout this entire period.


Near term /until 6 am Wednesday morning/...
skies remain mostly clear late this evening across all but
extreme eastern portions of central PA this evening. The western
extent of clouds continue to brush my southeast zones and will keep
bkn- ovc skies going overnight. Have removed shower mentions for
the overnight as well. Clouds associated with a weakening
frontal boundary will dissipate over far western PA overnight,
and the low level flow becomes light and northerly later
tonight as Jose weakens to a tropical storm and continues to
slowly drift off in a northeast direction. This will transition
US away from the stratus we saw this morning back to locally
dense valley fog for Wednesday morning. Min temps will be about
2-4f lower than early Tuesday over the northern half and similar
to Tuesday for the southern half - and notably milder than


Short term /6 am Wednesday morning through Wednesday night/...
after we burn off the fog in the valleys, a spectacular
Wednesday is on tap with abundant sunshine and just a few flat
cu and thin cirrus to paint the otherwise azure Blue Sky. Could
be a couple of showers off to our SW in a very weak and eroding
trough, but only result for US will be potentially an increase
in cloud cover over the Laurel Highlands.

Max temps will once again range from the upper 70s across the
higher terrain of the north and west, to the lower 80s (and
maybe a few mid 80s) in the southeast.


Long term /Thursday through Tuesday/...
overall pattern hasn't changed much, there is a good overall
consensus in the models through the second half of the work
week. For much of this period, a 590 dam closed 500 hpa high
will drift slowly out of the Midwest states, and become centered
over western PA by late this weekend through early next week.

The gefs forecasts showed this feature as a closed 5880 M ridge
over US with near +2 sigma above normal heights which will
translate to well above normal temperatures. High temps from
Wednesday and through the weekend will be 10-15f above normal
with little or no chance of rain through at least Monday.

Lows early each morning will be consistently in the mid and
upper 50s across the northern and western mtns, to lower 60s in
the larger southeast Metro areas.

Min temps may cool off slightly for this weekend thanks to deep
dry air and a light north to northwest llvl flow of drier dewpoint air at
the sfc.


Aviation /02z Wednesday through Sunday/...
widespread VFR continues this evening with generally light
winds. The western extent of the outer bands of light showers
associated with slowly weakening Hurricane Jose look like they
will just brush our southeast zones for a time this evening, but
no low conditions are expected even if they sneak into lns.

Low level flow will become light northerly tonight as Jose
weakens and meanders offshore overnight. This will transition
US away from the stratus we saw this morning back to locally
dense valley fog for Wednesday morning, which will likely affect
most terminals outside of the lower susq valley.

Wednesday we will start rather murky in the areas with fog,
before burning off to VFR conditions by mid to late morning.


Thu-sun...patchy valley fog possible each morning. Otherwise
VFR with generally light winds and minimal clouds.


astronomical fall/autumnal equinox begins at 4:02 PM Friday
September 22, 2017.


Ctp watches/warnings/advisories...



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