An Analysis of Rear-Flank Downdrafts Observed During Project ANSWERS

Matt Grzych
Texas Tech University, Lubbock, Texas

Project ANSWERS (Analysis of the Near-Surface Wind and Environment along the Rear Flank of Supercells) was conducted on the Central Plains during May and June of 2003. Four mobile mesonets collected high-resolution, near-surface data within six tornadic and six non-tornadic supercell rear-flank downdrafts (RFDs). Several RFD surges (or occlusion downdrafts), embedded within a larger scale RFD, were also sampled as well as high-resolution data near an F4 tornado. Analysis of this unique data set is currently being carried out using a time-to-space conversion method utilizing WSR-88D data and a GIS. Emphasis is being directed toward the comparison of RFD thermodynamics associated with tornadogenesis and tornadogenesis failure. Where applicable, thermodynamics of broad-scale RFD will be compared to those of embedded smaller scale RFD surges. The presentation includes a short overview of supercell dynamics, data collection and analysis techniques, and findings of the current research.

Matt Grzych is a candidate of our PhD Program