The first accumulating snow of the season has arrived in the DC metro region and it will move into the Philly metro region by late morning or early afternoon and then reach New York City by late afternoon or early evening. The general scenario at all three metro regions will be for a several hour period of accumulating snow followed by a several hour period with icing (i.e., sleet and/or freezing rain) and this will add a layer of ice on top of the snow. Finally, enough milder air will move in to change all of the precipitation to plain rain later tonight and early Monday from the immediate I-95 corridor to the coast. Areas north and west of I-95 will see a longer period of frozen precipitation perhaps into the early morning hours on Monday.
Snow accumulations of 2-4 inches can be expected across the DC metro region and I believe this 2-4 inch range, perhaps even isolated 6" amounts, will extend northward to the region between Philly and New York City based on current radar observations which suggest a heavier band of snow will set up later today in that region. Travel conditions will deteriorate for an extended period of time into the overnight hours in all three metro regions given the accumulating snow and ice and with surface temperatures holding at or below the freezing mark. By tomorrow morning, plain rain should help to improve travel conditions along I-95 and to the coast. Stay tuned, tricky forecast.
One final note, there will be snow and/or bitter cold across the board today for the NFL in places like Philly, Baltimore, DC, Green Bay, Denver, etc., etc.