Even discounting the broader metro, there are almost 9 million people living in NYC. It's unlikely that any meaningful fraction of them could possibly get out in the time between learning we were in a nuclear confrontation, and the first consequences of that confrontation for NYC.
> It's unlikely that any meaningful fraction of them could possibly get out in the time between learning we were in a nuclear confrontation, and the first consequences of that confrontation for NYC.
I imagine it's very likely the two would happen simultaneously.