Studies of Severe Convective Storms and Tornadoes

University Of Oklahoma Norman Campus, Norman OK

Investigators

Abstract

The goal of this research project is to understand better the dynamics of severe convective storms and tornadoes. This goal will be met through the analysis of observational data sets and from idealized numerical simulation experiments. Mobile Doppler radar data sets collected in tornadoes will be analyzed in detail and a small, focussed field experiment will be conducted to collect and analyze additional data in order to obtain a better statistical characterization of tornadoes and their environment. The main thrust of this effort will be to estimate wind speeds near the ground in tornadoes, determine the three-dimensional wind field in tornadoes, determine why tornadoes form and dissipate and find out why some supercell storms produce tornadoes, while others do not. Numerical simulation experiments will be conducted in order to understand the dynamics of an elevated rear-inflow jet and a counterrotating vortex couplet observed in an airborne Doppler radar analyses of a nontornadic supercell hailstorm. It is hypothesized that the vortex couplet was created through the tilting of horizontal vorticity by the downdraft in the storm. The importance of this study is that the rear-inflow jet and vortex couplet may be characteristic of a subclass of supercell storms. Successful completion of this research will lead to better conceptual models of tornadoes and tornado genesis and eventually lead to more accurate predictions.