NYC hasn't been below 0F since 2016 (-1F) and the last time before that was 1994 (-2F) and hasn't hit -5F or colder since 1943 (-8F). It used to regularly go below 0F every few years and now it's quite rare in NYC, due to the combo of the urban heat island getting worse and global warming.wasn't it much worse than this just a couple years ago when the term "polar vortex" was introduced to the public? I remember it hitting around -5 to -10 in NYC which generally is warmer than NJ state.