The 8 June 1995 McLean, Texas, Storm. Part I: Observations of Cyclic Tornadogenesis

Abstract

Abstract On 8 June 1995 scientists participating in the Verification of the Origins of Rotation in Tornadoes Experiment (VORTEX) collected airborne Doppler radar data in a storm that produced a family of tornadoes near McLean, Texas. The Electra Doppler Radar (ELDORA) scanned three significant tornadoes during their formative and mature stages; one of the tornadoes was of F4/F5 intensity. Evidence from pseudo-dual-Doppler analyses of the ELDORA data reveals a process of cyclic tornado formation qualitatively similar to that depicted in previous conceptual models. In particular, the rear-flank gust front appears to play a major role in determining the location of the next vortex in the series. When a tornado forms, a small region (3–5 km wide) of outflow surges ahead of the tornado, producing a local bulge in the gust front. A new vorticity maximum may form near the leading edge of the outflow. In contrast to what is suggested by earlier conceptual models, intersection of the rear-flank gust front with a w...