snowball's chance in hell
Definition from Wiktionary, the free dictionary
- (idiomatic, slang) Little or no likelihood of occurrence or success.
- That small boat has a snowball’s chance in hell of surviving the hurricane.
Often, the expression is used in the negative for even more emphasis (implying that the referent has even less chance of success than a snowball in hell).
- That small boat doesn’t have a snowball’s chance in hell of surviving the hurricane.
Little or no likelihood of occurrence or success