For the final snow map I am not going to change anything, this covers through tomorrow afternoon but I do want to say based on latest observations, that most of the forecast area from Philly to New York and Long Island should expect more towards the lower side of these totals . We have a lot of warm air advection off the water with temperatures rising into the 40s and the coastal low is a bit farther south than expected so precipitation tonight will likely be light to moderate instead of moderate to heavy by the time the change over occurs.
Our coastal low has taken over (currently a 994 mb low over SE VA) driving in a strong east wind, and we see mostly rain over spreading the area from SE to NW , some snow mixing in as you head towards north and west NJ
Most of the area will see rain become steady and soaking between now over southern NJ t0 2-4 pm for the rest of the area , and again a mix over NW NJ and East PA
Rain will gradually change over to wet snow after sunset and begin to accumulate on grassy surfaces, with much of the area between 32-35 degrees it will take very heavy snow to stick onto road surfaces besides NW NJ and higher elevations
Precipitation will wind down and become more scattered by tomorrow morning with snow showers interior and a mix along the coast of rain and snow showers.
Then a lot of uncertainty comes into play tomorrow , the storm is expected to stall off the coast and could throw back more snow tomorrow night , especially over the New York City area through northern NJ
This is called a norlun or inverted trough which develops due to the storm stalling off shore and interacting with another disturbance over the Great Lakes, these are highly volatile (just like this whole storm has been!!) and it will take perfect timing for this to occur but if it does we would see another round of steady precipitation tomorrow night and could add-on some light to perhaps moderate snow accumulations, I will know more about this tonight, the final snow map for now does not take this into account because of high uncertainty .
And of course winds will be a big issue through tomorrow night with the strongest winds and most significant coastal flooding tonight and tomorrow morning, the whole area will see winds sustained 15-30 with gusts to 45-50 (especially as you get closer to the coast) but along the immediate coast winds will be 25-35 with gusts to 60 , moderate coastal flooding from Sandy Hook NJ down to Delaware and minor to moderate NE NJ coast, and New York Coastline