Looking potentially very serious indeed for the eastern seaboard of the US, perhaps including NYC if some models are correct. The storm will probably be extra tropical but nevertheless if it interacts with a trough modelled off the east coast that could bring down arctic air then the result could be approaching catastrophic, with utterly torrential rain, severe blizzards, hurricane force winds and severe storm surges all being possible.
I think people will be getting very worried about this. Mon tues weds are the days to be watching. Lets hope the storm turns east away from the us coast.