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fxus61 kctp 281836 

Area forecast discussion
National Weather Service State College PA
236 PM EDT Tue Mar 28 2017

an area of low pressure will move along the Mason-Dixon line
through tonight...bringing showers to central PA and isolated
thunderstorms to southeastern sections today. High pressure
will build down out of southern Canada and bring cooler and
drier weather for Wednesday and Thursday.

A new storm system will approach for the end of this week with
the potential for more inclement weather.


Near term /until 6 PM this evening/...
still some areas of light rain over eastern areas and drizzle
with low clouds in central areas. But the main energy has moved
off to our east. GOES-16 shows all the cold cloud tops to our
east and cold conveyor lifting into New York.

A lot of dry air in western PA and the upper level low to our
south. So most of the significant rain is over. Gradual
improvement later this afternoon and evening.

Best probability of precipitation now in the eastern areas.


Short term /6 PM this evening through 6 PM Wednesday/...
the rain threat should mostly be off to our east by 8-10 PM.

Improving conditions as the strong anticyclone to our northwest
slides slowly over the area. Should be near seasonal day with
mostly sunny skies and little chance of quantitative precipitation forecast.


Long term /Wednesday night through Monday/...
the dry air and high pressure are in all of the most recent
guidance, implying Wed ngt and Thursday will remain dry and

High pressure, dry air, and normal to slightly below normal 850
hpa and 925 hpa temperatures imply near normal daytime highs.
Most of the 26/00-06z U.S. And int'l model guidance (and efs)
indicates more of southern...shearing storm track for late in
the week...thanks to a stronger and more wwd position of a deep
nrn stream vortex across the Canadian Maritimes.

The trend of the big model discrepancy for late this week and
this weekend (between the GFS and ec over the past several days)
has trended toward the GFS and its ens members with southern
stream energy and its moisture being prevented from amplifying
with an associated storm track to our west.

Rather, what we see is a shift of the primary southern stream
sfc low track to our south as the potent midweek southern stream
sfc/upper low (that will be trying to take the turn northeast
across the mid miss valley twd the great lakes) encounters great
resistance from the notably stronger west-northwest upper jet core
defining the northern stream that will be situated from the
upper glakes to the mid atl coast.

With this type of consensus storm track, pops will be somewhat
less for Friday and Saturday (compared to a heavily weighted
ec/ecens solution) and limited to mainly the southern half of PA
where some rain (or even an elevation-dependent rain/wet snow
mix) with expansive cooler and drier air north of PA.


Aviation /18z Tuesday through Sunday/...

Considerable areas of MVFR and IFR remain this afternoon,
however latest satellite image shower the sfc low moving
eastward. The rain, mist and fog should persist through this
afternoon though clearing has already begun at aoo. Upslope flow
will keep jst in IFR cigs and vsbys but west to east expect cigs
and vsbys to improve between 21z to 00z. MVFR could persist
until around 03z, especially at bfd.
The trend for improvement will continue overnight with fair
weather and VFR conditions tomorrow.


Wed...early a.M. Restrictions; becoming VFR.

Thu...VFR/no sig wx.

Thu night-Fri...sub-VFR restrictions/rain likely.

Sat...gradually improving conditions.


Ctp watches/warnings/advisories...



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