Is it normal for a cyclonic storm to form at the latitude of New York, USA?
A cyclone is nothing more than a low-pressure system. It can surely form in the North Atlantic; in fact, most low-pressure systems that reach Europe form in the North Atlantic.
You are probably thinking about a tropical cyclone, which indeed cannot form that far north. Among others, a tropical cyclone needs high sea temperatures (>27 C), which are usually not present at such high latitudes.

About the present cyclone south of Nova Scotia: I think it is a cold core cyclone, as 500 hPa temperature are lower than in surroundings (which is e.g. not the case for tropical storm Dorian, which is currently east from the Lesser Antilles). Therefore, it's not a tropical cyclone but an ordinary extra-tropical cyclone, which can perfectly form at those latitudes.