Abstract
Correlation and regression analyses were employed to evaluate the relation between summer hail patterns in Illinois and the climatological distribution of other meteorological elements, after dividing the state into sections with similar climatological characteristics. The distributions of thunderstorms, rainfall, maximum air temperature, dew-point temperature, and synoptic weather fronts were related to the hail distribution. Relatively strong association was found between the hail distribution and the combination of these five climatological elements, when multiple correlation analysis was performed and regression equations developed. The results of the study indicate that in a region of minor topographic influences, such as Illinois, the hail distribution can be explained largely by relating it to the multiple effects of other climatic events, whose distributions are determined by atmospheric conditions which are related to hail development. The Illinois study suggests that the frontal distribution pattern strongly influences the location of centers of maximum hail frequency.
