Analysis of cross-spectrum supercells during the north Georgia tornado event of 2 January 2006

During the afternoon and evening hours of 2 January 2006, six tornadoes were spawned across portions of north and central Georgia. The near-storm environment of this event was unique, characterized by an area of eroding cold-air damming in northeast Georgia, and a dryline approaching the state from Alabama. Though research on drylines in the Southeast is difficult to find, anecdotal evidence indicates that drylines such as the one associated with these tornadoes are truly rare events. Rarer still are the supercells that formed along the dryline; most supercells in the Southeast are high-precipitation in nature, yet one of the six tornado-spawning supercells was classic, and another was a low-precipitation supercell. This study focused on these two supercells that produced the strongest tornadoes of the day, an F2 and F3, respectively, and how they were influenced by the near-storm environment. Observations indicated that mesoscale features, such as the dryline and cold-air damming were critical in developing and maintaining this near-storm environment, and that cell mergers and/or interactions were precursors to tornadogenesis in every case.