There may be sun out right now, but the models are consistently showing snow to begin in PHL by 1 PM today. Latest NAM model has been consistent in cranking out a QPF of > 0.80 inches of water, with about 0.40 inches falling as snow. I’m still going with 4-7 inches of snow in PHL before a changeover to sleet and freezing rain.
The trend has been for an extended period of cold air at the surface to remain in place, even if the upper atmosphere warms a bit.
The changeover to sleet and rain will tamp down final snow totals however extended period of surface temperatures below freezing will likely cause extensive icing, especially north and west of Philadelphia. Driving later this afternoon and this evening may be very difficult. Large storm snow totals sound impressive, but this sort of snow to ice mix can be more dangerous.
I don’t think this is going to be a storm where the rain washes the snow and ice away.