3:15 PM | Snow begins early tonight across SE PA and pounds away from NYC to New England

Discussion

So far today’s storm has been primarily in the form of rain across southeastern PA and the main threat for snow won’t come until early tonight (probably after 6 or 7pm) when the wrap around moisture moves into the region as the phasing process completes between the northern disturbance and the coastal system. There is a rather narrow, but intense band of snow seen on radar in central PA that is associated with the strong northern stream trough and it should expand and slow down as it moves eastward into eastern PA. At the same time, colder air will be driving south riding in on increasing NE boundary layer winds. The rest of the afternoon may, in fact, have a precipitation pattern that is light and spotty as the coastal system slides to our east along with its precipitation shield, but then the “deformation zone” activity should begin early tonight (after 6 or 7pm) across SE PA. The wrap around band of moisture will actually stall once in reaches SE PA as the coastal storm continues to intensify and snow could fall at varying rates for much of the night. Accumulations have been reduced back down to the 2-6 inch range with two inches expected to the south and west and 6 inches to the north and east (e.g. Bucks County). Snow has been falling for the past several hours across parts of northern New Jersey, the NYC metro region, and southern New England and this is the area that will bear the brunt of the storm overnight with blizzard conditions and 1-2 feet of snow in many places. Heavy rain and thunderstorms have been falling for the past few hours in southern and central New Jersey.