A Tale of Two Supercells: The Randall County storms of 16-17 October 2007

In the late evening and early morning hours of 16-17 October 2007, a pair of supercell thunderstorms developed south of Amarillo, Texas and moved northeast across southern portions of Randall County. Although severe thunderstorms are not unheard of in the Texas Panhandle in autumn, the unusual aspect of this event is that both storms exhibited strong low-level rotation and featured hook echo signatures, prompting WFO Amarillo to issue tornado warnings for both storms shortly after midnight. However, based upon damage surveys of the tracks of both mesocyclones, only one of the storms produced a tornado, which was continuous for 20 minutes during its nearly 12 mile, up to 300 yard wide, path across southern Randall County.

The proximity of these storms to the Amarillo WSR-88D afforded a more thorough analysis of these two storms than is often possible. Apart from a summary of the weather conditions that led to the generation of the storms, this paper will examine, and highlight differences in, the structure of the two storms as depicted by radar imagery, to present some potential considerations for future tornado warning decisions.