Climatology of Tropical System Rainfall on the Eastern Corn Belt

This study explored the climatology of heavy rain (i.e., equal to or greater than 1 inch in a 24 hour period) producing tropical systems that impacted the eastern Corn Belt during the months of June through October. From 1913-2012, the remnants of 60 tropical systems moved into a region that included 24 climate divisions (CD) located in Illinois, Indiana, and western Ohio. Of those 60 tropical systems, 37 were associated with heavy rain producing events in this critical crop growing region. The resulting 100-year (1913-2012) climatology showed that infrequent heavy rain producing tropical systems had a very small impact on corn and soybean growing season conditions as they occurred primarily in September (21 of 37 events). Events had some impact on CD average soil moisture conditions, however, these events did not occur more frequently during dry conditions (i.e., no drought-buster signal found). A decadal analysis of tropical systems and events showed a dramatic increase in both during the most recent decade. A synoptic analysis of the 60 tropical systems identified several differences between events and non-events leading to potentially important forecast information for those working with Midwestern agricultural decision makers.