In April the Southeast endured more tornadoes in a single day than in any other 24-hour period in U.S. history. At least 312 tornadoes swept through seven states April 27, killing at least 345 people.

After touring Tuscaloosa, Ala., President Barack Obama said, "I've never seen devastation like this." Farther north, a May 22 tornado swept through Joplin, Mo., killing at least 134 people-the worst death toll from one tornado since 1947.