Area Forecast Discussion
Issued by NWS State College, PA-- Remove Highlighting --
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FXUS61 KCTP 252226
Area Forecast Discussion
National Weather Service State College PA
626 PM EDT Sun Sep 25 2016
A large area of high pressure over the area will result in
another cool night across the Keystone state. Low pressure will
move into the Upper Great Lakes on Monday, and push a cold front
through the region by Tuesday morning. The forecast becomes less
certain for the rest of the week as a cut off low forms over the
eastern United States. Cooler and at times wet weather will
prevail for the later part of the week.
.NEAR TERM /UNTIL 11 PM THIS EVENING/...
Been watching an area of clouds over VA. Time of day and strong
heating has push the leading edge of the clouds away from south
central PA. A fine early fall evening will prevail outside.
.SHORT TERM /11 PM THIS EVENING THROUGH MONDAY NIGHT/...
Expect some clouds to edge back north from VA late tonight into
Monday. A rather cool airmass is at low levels, and given timing,
hard to see a large rise in temperatures on Monday, even with
850 mb temperatures still on the warm side. Thus did lower max
temperatures a little.
SPC has MRGL outlook for the far west on Monday. This looks ok.
While more heating will be likely to the east, it will be less
Did adjust pop and weather groups some. Not looking at a lot of
rain, but expect some across most of the area.
.LONG TERM /TUESDAY THROUGH SUNDAY/...
The mid week period will bring the large upper level low through
the Great Lakes and down into the Ohio Valley. This will keep cold
air advection through the region...keeping temperatures slightly
below normal. The low will slowly progress eastward with model
PWATS increasing through the latter half of the week. Couple this
with the Southwesterly flow and will allow for an increase of
POPS Through the second half of the week and into the weekend. The
biggest question becomes what will be the progression and timing
of the upper level low. Some runs of the GEFS have it opening up
into a wave and a few have it retrograding westward. So what may
have been yet another dry period could turn cooler and wetter - or
at least cloudier in the latter half of the period. So given this
uncertainty have increased POPS through Friday.
.AVIATION /22Z SUNDAY THROUGH FRIDAY/...
-- Changed Discussion --High pressure over the region will ensure clear skies and light
wind this evening. However, as the high slips off the Mid Atlantic
coast late tonight, an increasingly moist se flow will likely
cause low cigs to creep northward from Virginia into the Laurel
Highlands. Latest model soundings support the idea of IFR cigs at
KJST and mvfr cigs at KAOO by around 09Z.
The odds of IFR cigs at KJST should decrease by midday Monday,
as the wind shifts from se to a downsloping south wind.
Elsewhere, stratus should expand to cover most of the region, with
MVFR or low VFR cigs anticipated based on model soundings. A cold
front will approach from the west late in the day, but expect
associated showers and thunderstorms to hold off until the evening
Tue-Fri...A chance of showers, most of the time it should be dry.
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