When an individual has a 'gut feeling' something bad is going to happen without there being any sort of reason for them to believe that. This would also be used to describe when someone randomly gets the goosebumps or chills out of nowhere.
Saying it (and meaning it) will immediately result in the eruption of laughter from all people in the vicinity.
However, overusing the phrase will result it it losing its magical laughter-inducing powers. It does not always work, unless it is said and absolutely meant.