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Area forecast discussion 
National Weather Service State College PA
209 PM EDT sun may 3 2015


High pressure over the southern Appalachians will drift east and
off the Carolina coast tonight. A developing southwesterly flow
will lead to warmer temperatures that will continue through at
least the middle of the upcoming week.


Near term /through tonight/...

Heating has caused the development of some fair weather cumulus and
Alto-cu. Otherwise its a fine late Spring day with temperatures
generally in the 70s.

We should lose the clouds with the loss of heating. Lows will drop
back into the middle to upper 40s.


Short term /Monday/...

Monday will feature morning sunshine followed by more diurnally
enhanced afternoon cumulus. Any chance for a shower or thunderstorm will
be across the northwest mountains and limited to late in the afternoon
and evening as a cold front sags southeast from the glakes.

Highs Monday will rise into the middle 70s to lower 80s.


Long term /Monday night through Sunday/...
shortwaves tracking east across southern Canada to north of the
Great Lakes will help push a backdoor-style surface cold front into
central or southern PA by early Tuesday. The front will waver near or
more likely just to the south of the Mason-Dixon line into the
middle of the upcoming week...and will serve as a focus for
clouds and showers mainly along and north of the boundary.

The latest ensemble data shows above normal precipitable waters along the east-west
frontal zone which is usually a good indicator of at least climatology
or better probability of precipitation but due to the north-S model quantitative precipitation forecast differences will utilize
a blend and cap probability of precipitation around the high chance level /40-50 percent/ for
days 3-4.

From the middle to later part of the week...the global numerical
model and ensemble guidance shows low pressure moving east from
the northern High Plains to the western Great Lakes/upper Midwest
by Friday. This should allow the western portion of the east-west frontal
zone to be lift northward through the Ohio Valley while the eastern segment
weakens and wavers just west/south of the PA and Ohio/WV/MD borders.
In general the precipitation pattern should be more Summer-like with weak
forcing under high heights aloft and scattered diurnal shower/isolated thunderstorm
activity near the boundary and perhaps initiating over the western high
terrain. Therefore kept probability of precipitation in the schc to low chance range Wednesday-Friday
with gradual increase into the weekend as the plains frontal
system approaches.

Temperatures should average near to above normal through the period.


Aviation /18z Sunday through Friday/...

Expect VFR conditions to continue through Monday. A taste of fine
Spring weather.

An approaching cold front may trigger some showers across
north central PA Monday night into Tuesday. The front will likely
slow and create low ceilings/showers into Wednesday. The front may push to
the south on Thursday.


Tuesday...showers/thunderstorms and local reduced conditions.

Wednesday...continued showers and areas of MVFR/IFR. sig weather.


Ctp watches/warnings/advisories...


$$ corte
near corte
short corte
long term...Lambert/steinbugl corte

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