Synopsis:

Wednesday will be rather calm with a mix of clouds and sun. Tropical depression 16 (possibly to become Nicole), is currently crossing Cuba, will interact with an east coast trough to bring a drenching rain throughout much of the commonwealth on Thursday. After this clears out early Friday, a strong trough will bring about the coolest weather of the season thus far.  Clouds will decrease by the end of the day Friday.  Partly cloudy skies will be seen this weekend with temperatures well below average.

Short term (Wed/Wed night):

A weak high pressure will be over the state during the day Wednesday with calm winds.  There will be a mix of clouds and sun.  This will be short live though as a vort max shifts southward combining with the tropical disturbance near Cuba and Florida.  This system will push northward bringing with it copious amounts of moisture.  Most areas will be overcast by late evening as high RH move into the 700 & 850 levels. 

Long Term (Thursday – Sat)

As the extra tropical system pushes northward, a deep trough is clearly visible over the eastern half of the country.  This trough is responsible for the unseasonably cold weather that will be seen this weekend.  Both the WRF and GFS show precipitation beginning between  2-8 am on Thursday.  As of now, it seems that most ensemble members project for the center of the Low to go right across the center of Pennsylvania near Centre County.  The SREF plumes show that most regions (minus the NW) have mean /median ensemble rain amounts of around three inches.  The min ensemble members in most areas are above 0.5.  Some members say up to 5-6 inches by the end of the storm.  I'd say that many areas will likely see at least two inches of rain.  Exact amounts will depend on track of storm.   Rain will taper off early Friday morning.  Partial clearing will occur Friday afternoon as dry air moves into place, along with chilly temperatures.  Continued NW flow will continue CAA into the region through the weekend.  The GFS pushes the 540 line well below the state into Northern Virginia.  Partly clouds skies will be seen over the eastern portion of the state this weekend.  Areas in the west could see more cloudiness due to the flow over the lake.  Some areas could experience lake effect showers. 

Dan the man the weather man dan Pollak