A severe weather and tornado outbreak happened between December 10 and 11, 2021. In the outbreak, there were 71 tornadoes involved, along with severe thunderstorms traveled across the U.S. states of Missouri, Arkansas, Kentucky, Illinois and Tennessee.
Across Kentucky, Missouri, Tennessee and Illinois, the tornado sequence carved a path of 166 miles. It was the longest tornado since 1925 Tri-State tornado. The starting report on several tornadoes is that they were EF4.
89 people were confirmed killed by the outbreak. The Governor of Kentucky (at that time) stated that beyond seventy people might have been killed in the state alone.