Dumbest movie,you have ever seen.... (Facepalm stuff...).

The Day after Tomorrow.

Totally impossible to flood NYC and then have it freeze in just a few hours. The energy transfer rate would be so incredible (High Wind and incredibly low ambient temperature) that no human could ever survive it. It would also have to be being transferred somewhere else or the sun would have to stop burning.

It's also a "scare you into our agenda" movie which makes it even worse.