Bill left Michigan at 2AM and picked up fellow tour guide Sean Lyon in Chicago. They lost one hour due to Chicago area rush hour. A data call for surface observations made it very clear where to go. There was a nice triple point over northeast SD, this was a bit farther north than Bill's original forecast, which had been northwest Souix Falls. Luckily They made it up in time for the tornado.
Tornado has violent rotation.
Tornado ropes out. The same tornado reforms. This tornado will continue for an extra 5 minutes. May 8, 1993. During one of the most incredible tornado-filled weeks of chasing ever, a classic, cyclical supercell produced mostly weak tornadoes from near Archer City, TX to northeast of Ryan, OK where these brief but striking tornadoes occured.