Investigation of the Variability of Extreme Tornado Climatology
AdvisorDixon, P. Grady
CommitteeMercer, Andrew E.
Cooke, William H., III
Previous tornado climatology research has relied primarily upon means of tornadoes or tornado days. Understanding the variability of tornado days however, will result in a more comprehensive understanding of the climatological distribution of tornadoes. In a changing environment, the extremities of a distribution should change faster than the mean of that distribution. Two methods of analyzing tornado days for predefined areas across the continental United States using the Storm Prediction Center's publication Storm Data from 1950 to 2011 are conducted in this study. Statistical analysis of averages, return periods, and percentiles reveals the variability in the record while consecutive tornado days present an alternative way to assess the seasonal repeatability and to assess risk for historic, multi-day tornado outbreaks. The results of this research will help to better define the traditional “tornado alley” as well as highlight other high-risk locations, especially those with higher interannual variability.