On April 11, 1991, a canceled check was sucked up by a tornado in Stockton, Kansas. It was carried 223 miles to Robert Melcher’s farm near Winnetoon, Neb. John Knox, an associate professor of geography at the University of Georgia, is conducting research on how debris is carried by twisters to better understand the intricacies of this weather phenomenon. Knox and his students categorized items by weight, such as a Hackleburg, Ala., high school cheerleading jacket that flew 66 miles to Elkmont, Ala., during a tornado outbreak. On April 27, 2011, more than 120 tornadoes caused 300 deaths across the South and retrieved items were compared with the direction of the storms. Regardless of weight, researchers determined most of the debris fell slightly left of the storm’s track. Fastcast: Spotty showers.