A Guide to What Your Cat is Communicating: A cat's tail is far more than just a balance toolit is a sophisticated emotional barometer that broadcasts their internal world. When your feline Cat tail signs: What your cat's tail tells you It looks like they are vibrating. When a cat's tail shoots straight up and quivers or rattles at the tip, it is the highest form of excitement they can show. It's a Why Do Cats Vibrate Their Tail? This Is What They Might Be Signalling With It We Love Catz How to Read Your Cat's Tail Language