Persistent Patterns of Thunderstorm Activity in the Central United States

Abstract

Observations of thunderstorm events by mouth for the period 1948?77 at 106 stations in the central United States are used to examine persistent spatial patterns in thunderstorm occurrence. A principal components analysis reveals that nearly 55% of the variance is explained by the first four components. An oblique rotation was performed using the first four components, with distinct synoptic-scale patterns revealed. The synoptic environments of four months representative of the four rotated components arc briefly described. A regionalization is presented that was developed by assigning each grid point to the rotated component on which it has the highest loading.