The last EF5 storm, the weather service’s maximum level, to hit the USA was in 1997. The EF5 that hit Greensburg, KS on May 5, 2007 was on the ground for 30 minutes as it left a path of destruction for 22 miles throughout SW Kansas. Wind speeds exceeded 200 mph!
There are several websites that have some incredible pictures of the aftermath of the Greensburg storm. I hope to never go through such a storm myself.