An experiment was conducted in which an image-intensified, low-light video camera systematically monitored the stratosphere above distant (100--800 km) mesoscale convective systems over the high plains of the central U.S. for 21 nights between 6 July and 27 August 1993. Complex, luminous structures were observed above large thunderstorm clusters on eleven nights, with one storm system (7 July 1993) yielding 248 events in 410 minutes. Their duration ranged from 33 to 283 ms, with an average of 98 ms. The luminous structures, generally not visible to the naked, dark-adapted eye, exhibited on video a wide variety of brightness levels and shapes including streaks, aurora-like curtains, smudges, fountains, and jets. The structures were often more than 10 km wide and their upper portions extended to above 50 km msl. ¿ American Geophysical Union 1994