I was 10 on a family road trip from Georgia to Minnesota at a KOA east of madison when this front rolled through we were eating dinner on the patio outside of the restaurant as boiling green clouds about 100 feet off the ground rolled over us. I remember the temperature dropping and my ears popping from the pressure drop and it got dark really fast. Suddenly we were racing to take our pop up camper down hitch it to our Volkswagen camper van and trying to find the nearest motel in the second most intense storm id ever seen(i was in Richmond hill/savanna ga for cat 5 hurricane David 1979, snapped 6 pine trees in our yard). Ill never forget that day.