It means the same as any other person who says it. "A few", as in, maybe 3 to 5 years. That's why he said children won't know what snow is. If they were small children in 2000 then by 2003 snow is gone, they won't remember it.

But yea, sure, if you want to argue that he wasn't speaking English and that "Children just aren't going to know what snow is" didn't happen then go for it, that'll be amusing to read.