Not to be Captain Obvious here, but a tornado over water is called a waterspout. As soon as it moves onto land, it’s called a tornado. On May 8th, a waterspout made landfall in Grand Isle, Louisianna, and began ripping apart buildings. While this isn’t necessarily uncommon, the video below is astounding as the buildings begin to shred. To my knowledge, there were no reported injuries despite the damage. The gentleman taking the video was very lucky he didn’t become part of a tragic story.
The tornado damage begins around the 4:25 mark in the video.