Examples:

There’s not a snowball's chance in hell that I can finish this report by the deadline.

Why do you keep playing the lottery? There's not a snowball's chance in hell that you're going to win so why don't you put your money in savings account instead?

I didn't think there would be a snowball's chance in hell that it would snow in May but look out the window.

I know you want to be an actress but there's not a snowball's chance in hell that you're going to get work without an agent.

He doesn't have a snowball's chance in hell of getting the job.

If he can't afford a good lawyer, he doesn't have a snowball's chance in hell of winning the case.

He hasn't got a snowball's chance in hell of getting a date with Britney Spears but let him keep his fantasy.

Let's be honest—there isn't a snowball's chance in hell that we'll win this game.