a New York minute

A very short amount of time. Typically used to indicate that something will happen immediately or very quickly. A reference to the notion that things happen at a more rapid pace in New York City. I'd quit my job in a New York minute if I ever won the lottery. Phil's single again? Man, I'd go out with him in a New York minute—think you can set us up? Who wins an all-expenses-paid trip to the Bahamas and doesn't take it? If it were me, I'd be out of here in a New York minute!

a New York minute

a very short time; a moment. US informal

a New York ˈminute

(American English) a very short period of time; very quickly: Everything can change in a New York minute. ♢ I loved the hotel and would stay there again in a New York minute!

This may refer to the idea that everything and everybody moves quickly in New York.