The National weather service in Philadelphia has now issued a Snowstorm warning for Mercer County from 4 AM to 7 : 00 Pm Sunday. Heavy snow expected. Total snow accumulations of 4 to 7 inches. Travel could be very difficult particularly late Sunday morning and early Sunday afternoon. A heavy band of snowfall will overspread the area Sunday morning, with snow continuing into Sunday afternoon. Snowfall rates of 2 in/hr will be possible within this heavy band, and isolated snowfall totals in excess of 7 inches will be possible. Snowfall will clear the area from SW-NE Sunday afternoon.