Nine years ago this week, an EF5 rated tornado that destroyed a large part of Joplin, Missouri. The storm killed 160 people and injured well over a thousand. It is the most deadly tornado in the United States since the Woodward tornado killed 181 in Oklahoma and Kansas in 1947. A month before the Joplin tornado, 324 people died from tornadoes across the South in a three-day tornado super outbreak centered on Alabama. The total number of tornado fatalities in the United States in 2011 was 553, making it the deadliest year for tornadoes since 1925.
Since 2011, the average number of tornado fatalities throughout the United States per year is 39. In the ten years before 2011, the average annual tornado death toll was 45. This illustrates what an extraordinary year 2011 was for tornadoes. There were a lot of tornadoes and several of those tornadoes moved through cities with high populations.