An extended period of significant tornado activity affected the Midwest and Southern United States from April 19 to April 24, 2011, with 134 tornadoes being spawned across six days. The outbreak produced an EF4 tornado that tore through the St. Louis metropolitan area on April 22, while other tornadoes caused damage in Illinois, Indiana, Ohio, Kentucky, Texas, Oklahoma, and other parts of Missouri during the period. No fatalities were reported in this outbreak. This event was directly followed by the largest tornado outbreak in the history of the United States.