Currently: A stationary front extended from the Blue Ridge mountains up into the Susquehanna Valley. This front has become the focal point for showers and thunderstorms, some with heavy rain. This front passes through Friday, with some severe weather possible. However, that front will then become the new focal point for more showers and thunderstorms early next week.
Tonight: A warm and muggy night. Low temperatures probably don't get below 70 for much of the state. Temperatures should be fairly close to guidance. Used the NAM guidance for a background for temperatures. Showers and thunderstorms should be scattered to numerous throughout the night, perhaps tapering off for a few hours toward morning. Any storms could contain heavy downpours. Since the front is still hundreds of miles away, severe weather is not a threat.
Tomorrow: I am cautiously going below guidance for temperatures tomorrow. Guidance seems pretty aggressive, and those levels are attainable, given full or mostly sun. However, it is curious that the same guidance that produces such warm temperatures also has fairly high POPs for precipitation. Therefore, tomorrow's temperatures are a bit tricky. Temperatures could spike up, then a heavy rain shower moves in and quickly lowers the temperatures. I think 80 to 85 degrees is a good forecast right now, but there could be wide and uneven distributions between areas that rain and do not rain. Storms will not be as widespread tomorrow, and should be more terrain and diurnally-induced. Still, showers and thunderstorms are basically possible at any time at any place.
Tomorrow Night/Friday: There should be a relative lull in the action later tomorrow night and early Friday as a small area of subsidence moves in. Even so, a widely scattered shower or thunderstorm cannot be completely ruled out. Later in the day Friday, as a fairly strong cold front enters this very humid, unstable air mass, thunderstorms will develop, probably in lines or line segments. These storms will be capable of producing large hail and/or damaging winds. In addition, given relatively slow steering currents and the very moist air mass in place, very heavy rain will also be possible with these storms.
Long Term (the weekend and beyond): High pressure behind the frontal system will build in and give the area a decent weekend. It now appears there very well may not be any rain at all this weekend. High temperatures should be in the mid 80s Saturday and Sunday. The weather should also be dry for most of Monday, with temperatures a couple degrees cooler than those of the weekend.
Beginning with Monday night, the showers and thunderstorms should return in full force. Right now, some of the models want to concentrate a period of Monday night and Tuesday morning for the main shower and thunderstorm threat. However, given the warm and humid nature of the air mass, the strength of the Bermuda Ridge, which would tend to slow frontal systems down, and the base pattern, I would find it very hard to believe that this period is limited to just a few hours of rain. So we'll maintain scattered showers and thunderstorms in the forecast for Tuesday and Wednesday, with temperatures in the low to mid 80s.
Looking into the long range, models are having a hard time resolving the exact placement of basic features, which is to be expected at this range, but the general theme is the continued fight between the Bermuda Ridge and any frontal systems that try to push into it. This results in a stormy, warm, and humid pattern for the area.