On March 23, 2012 low pressure spinning over Missouri sent waves of showers and thunderstorms eastward through the Ohio Valley for much of the day. By early afternoon a pocket of strong winds aloft rotated around the low and entered Kentucky just as a small line of convection developed roughly along Interstate 65. As the line of showers moved to the northeast, it may have crossed a subtle boundary that helped add just enough spin to the atmosphere to allow a couple of very narrow, brief tornadoes to form. The cells that spawned the tornadoes were very small, reaching only about 20,000 feet into the atmosphere (summertime supercells can grow to more than 50,000 feet tall). There wasn't even any lightning, as evidenced by lightning detection networks as well as storm witnesses who reported no thunder before the tornadoes struck.
On the map below, click on a track (thick red line) on the map below to see detailed information about each tornado.