1:15 PM | *In like a lion...out like a lion*

[Mid-day NEXRAD radar image; courtesy University of Wisconsin, NOAA]

Discussion

Here we are on the last day of March and accumulating snow is falling across much of central and northern Pennsylvania from a fast-moving, but potent "clipper-type" of system that contains plenty of moisture. State College, for example, is reporting big, heavy, wet snowflakes at the mid-day hour and grassy areas are already covered. The same story may develop later today and early tonight from east-central PA to interior NW New Jersey. A blob of precipitation seen on NEXRAD radar is moving southeastward across Pennsylvania at mid-day and it will arrive later this afternoon in SE PA and New Jersey. A chilly rain will develop across SE PA during the next few hours and there can be snowflakes mixed in; especially, in areas well to the north and west of the city of Philadelphia. In areas north of Route I-80, snow is likely to be the predominate form of precipitation this afternoon with a few inches possible in higher elevation locations such as the Poconos and interior NW New Jersey.

By early tonight (forecast map below), as low pressure pulls off of the Mid-Atlantic coastline, colder air will shift to the south and east and the odds of seeing snowflakes mixed in with the rain will increase notably even in the nearby suburbs of Philly. There is even an outside chance that some Philly suburban locations change to all snow before the precipitation winds down later this evening with possible small accumulations on grassy surfaces. The precipitation winds down later tonight and overnight lows will drop to near 30 degrees in the Philly suburbs. By the way, the same threat exists for small grassy snow accumulations later today and early tonight to the north and west of the NYC metro region; especially, across interior higher elevation locations of NW New Jersey. April begins tomorrow on a cold note with temperatures well-below normal for this time of year despite plenty of sunshine, but there will be a significant warm up on Thursday and Friday before more colder-than-normal air returns for the upcoming Easter weekend.

[12Z GFS forecast map for early tonight (blue=snow, green=rain); map courtesy "tropicaltidbits.com", NOAA]