Many debris balls – intense quasi-circular pockets of radar return associated with Tornado Vortex Signatures - showed up on radar in association with tornadoes during spring 2011. Not every tornado, however, had this signature. A number of these signatures, including those on April 27, 2011, are examined in four dimensions and compared to tornado damage paths. The data are examined to identify factors that determine the presence or absence of debris balls and variations in their radar reflectivities.