Some Possible Mechanisms for Tornadogenesis Failure in a Supercell During VORTEX

 

David O. Blanchard

NOAA/NSSL and OU/CIMMS

325 Broadway N/C/MRD

Boulder, Colorado 80303

Phone: 303/497-6693; Fax 303/497-6930

Email: blanch@ucar.edu

 

The Verification of Rotation in Tornadoes Experiment (VORTEX) was conducted in the southern plains of Kansas, Oklahoma, and Texas during the spring months of 1994 and 1995. A primary goal of the program was to collect data using multiple platforms that would then be analyzed to test and possibly refute various tornadogenesis hypotheses. On June 8, 1995, VORTEX scientists were able to collect excellent data on a strong, long-lived non-tornadic supercell near Elmwood, Oklahoma. The analysis of this storm is presented as an example of tornadogenesis failure.

Doppler radar data from the airborne NCAR ELDORA and the ground-based Doppler on Wheels (DOW), along with the surface mobile mesonet and Mobile-CLASS sounding systems were used to collect data while near and underneath the storm. The high spatial and temporal resolutions of these data allow for a detailed analysis of the three-dimensional wind field of the storm. Comparison between this non-tornadic supercell storm and other tornadic storms sampled in VORTEX clearly illustrate that many of the relevant features to the tornadogenesis process are present in this storm. An analysis of the dominant circulation features, the evolution of the rear and foward flank downdrafts, the cyclonic/ anticyclonic circulation couplets, surface boundaries, and other features of the storm will attempt to determine the causes of tornadogenesis failure.