Spatiotemporal Shifts in Tornadic Activity of 1958–2017 in the Central United States

Abstract

Research in the last several years has revealed a number of interesting trends, such as a eastward shift in tornadic activity away from ‘Tornado Alley’ southeast into ‘Dixie Alley’ and a decrease in the number of tornado days paired with an increase in the sizes of tornado outbreaks. The purpose of this study seeks to reaffirm some of those findings. It accomplishes this by aggregating the tornado records of 1958–2017 into multiple time periods and finding the centroid of the tornado distributions during each of those time periods and compares them to one another. In doing so, this study reaffirms the significant eastward shifts in tornadic activity found by the literature, finds little consistent evidence of a northward shift in tornadic activity, and reveals interesting monthly and annual differences in the total variability of tornadoes that has not been substantially discussed within the literature thus far.