Dual-Doppler Analysis of Two Tropical Cyclone Tornado Cases

As Tropical Cyclones make landfall, they pose many challenges to forecasters. Storm surge and wind damage are among some of the most damage-causing factors, but the often less-thought-of factor of tornadogenesis can still be deadly and cause significant harm. However, it is often very difficult to determine whether a specific tropical cyclone will produce a prolific amount of tornadoes, or only a few.

This study is two part: the first part will extend the tropical cyclone tornado database that was created by Schultz et al. (2009) from 2008 to 2015. The previous study investigated five factors that are relevant in tropical cyclone tornadogenesis. Those five factors will be repeated for the extended database but with further investigation.

The second part examines two cases in which the University of Alabama in Huntsville Mobile X-Band Radar deployed: Tropical Storm Fay in 2008 and Hurricane Isaac in 2012. Dual-Doppler Analysis was performed on the primary rainband of Fay, which was responsible for producing more than half of her tornadoes, and a tornado-warned distant supercell of Isaac. The primary goal of this study is to investigate rainband orientation of the tropical cyclone to the coast upon landfall to see if tornadogenesis is more prominent in one scenario rather than the other.