What is a hyperbole about hot weather?

A hyperbole is a figure of speech an author might use when he or she wants to exaggerate something, to make a situation sound far more drastic than it actually is. It is used for dramatic purposes - the thing being exaggerated isn't exactly as terrible as it sounds.

For example: It was so hot outside that I started to melt.

You didn't actually start to melt - it was just so hot that you felt like it.