In April 27, 2011 a deadly tornado moved through Tuscaloosa, Ala. Rotating thunderstorms – known as super cells – spawned at least a hundred twisters, which barreled through six Southern states and killed at least 283 people. National Weather Service, starting April 2012, is using a new tornado warning that's intended to scare eople into seeking shelter.
PHOTO: Dusty Compton/The Tuscaloosa News/AP/File
