Doppler Radar Observations of a Left-Moving Supercell Thunderstorm on 26 May 2009

Radar observations of a left-moving nontornadic supercell obtained by two Doppler on Wheels (DOW) radars on 26 May 2009 near Dallas, TX, during the Verification of the Origins of Rotation in Tornadoes Experiment 2 (VORTEX2) are presented. Single-Doppler observations began while the storm was a mature left-moving supercell and continued for approximately half an hour, after which time a second radar also began scanning the storm. Dual-Doppler observations lasted for about an hour, during which time a right-moving updraft began to develop on the flank of the original storm, which also acquired right-moving characteristics. Single-Doppler observations of the reflectivity and radial velocity fields in conjunction with surface, upper-air, and WSR-88D observations will be used to diagnose the hydrometeor, flow, and vorticity fields near and within the storm. Subsequently, these observations will be used to deduce possible reasons for the development of right-moving characteristics within what was originally a left-moving supercell.