Documentation of a Rare Tornadic Left-Moving Supercell

Abstract

An F1 anticyclonic tornado (i.e., clockwise rotation in the Northern Hemisphere) was produced by an intense left-moving/anticyclonic supercell near Rushville, Nebraska, on 20 June 2006. This is only the fifth formally documented left-moving supercell that produced an anticyclonic tornado. The left-moving supercell exhibited an impressive hook echo, mesoanticyclone, and bounded weak-echo region at the time of tornado occurrence—rivaling those of its right-moving counterparts. Since tornadic left-moving supercells are extremely rare, and thus potentially difficult to recognize, this paper serves to document the radar characteristics and environmental conditions of this event.