Oklahoma's preliminary tornado count for 2013 stands at 79, according to the National Weather Service. Fifty-six tornadoes happened between May 19 and May 31, including the violent EF5 tornado that tore through McClain and Cleveland counties, killing 23 people. Seven students were killed at Plaza Towers Elementary school in Moore. The May 31 tornado that struck Canadian County was the widest in recorded history at more than 2.6 miles across. Eight people were killed and hundreds injured. Flash flooding killed another 15 people across the state last year.