Wednesday Midday

Synopsis: A stronger cold front will be slowly pushing into the region this afternoon.  The front will become stalled as two short waves develop in the southwest, providing several wet days.  An upper level low will become cut off from the jet stream, which will help/enhance precipitation across the region as those two short waves move up the coast.

Short-term:  A matured low pressure system is in the Upper Great Lakes, with an associated strong cold front streaming to the south.  A short wave is providing showers to the Southwest portions of the country.  The clash between the front and shortwave will be over Pennsylvania for Wednesday night in terms of scattered showers and storms.  The upper level low associated with the mature low pressure will start to cut off from the jet stream and dive into the Great Lakes and Ohio River Valleys.  Showers/storms from overnight will end early Thursday morning, and majority of the region should be dry and cloudy for the rest of the morning and early afternoon.  As evening starts to roll in, showers and storms will redevelop as the strong cold front finally pushes through the state. 

Long-term:  After the evening showers on Thursday, the skies will remain cloudy but dry.  Another short wave will develop in the southwest parts of the country.  The timing and intensity of the showers and storms are different on the GFS and NAM.  The NAM shows the heavier precip to the west and south of the state as of 18z Friday, while the GFS shows the heavier precip to the west and east of the state, ready to enter New York and New England at 18z.  The overall picture looks like someone on Friday will see heavy rain, but location is still to be determined.  This will continue overnight, but the GFS shows the showers diminishing, while the NAM shows central PA getting the heavy showers.  Forecast went with scattered showers overnight to cover the bases.  Saturday the cut off low remains to the east, according to the GFS, and showers will pester the state for the morning and early afternoon, before a dry night.  Sunday looks to be dry, before showers redevelop from the south for the evening.  These showers look to be on the heavier side according to the GFS, but it is still too far out in the future to confirm.

Keeping temperatures near midnight's shift.