U.S. National Oceanic and Atmospheric Administration
1974: In what becomes known as the "Super Outbreak," 148 tornadoes are confirmed in 13 U.S. states, including Illinois, Indiana, Michigan, Ohio, Kentucky, Tennessee, Alabama, Mississippi, Georgia, North Carolina, Virginia, West Virginia, and New York. The event, at the time the biggest tornado outbreak in recorded history, left 319 dead, injured more than 5,000 and extensively damaged about 900 square miles along a total combined path length of 2,600 miles. The tornado outbreak wouldn't be surpassed in size until the April 25-28, 2011, tornado outbreak that left 324 dead across the Southeast, Southern Midwest and Northeast parts of the U.S. Pictured here is a "Super Outbreak" tornado that hit just west of Cincinnati. The tornado was rated as an F5, one of two F5s on that day that struck the Dayton-Cincinnati area.