The Relationship between Severe Weather Warnings, Storm Reports, and Storm Cell Frequency in and around Several Large Metropolitan Areas

Abstract

AbstractThe spatial distribution of storm-based severe weather warnings, local storm reports, and radar-detected storm cells around six large cities in the central United States is examined from October 2007 to May 2017. The cities are Columbus, Ohio; Cincinnati, Ohio; Indianapolis, Indiana; Louisville, Kentucky; Nashville, Tennessee; and St. Louis, Missouri. In all six cities, warning counts within 20 km of the city center are found to vary by 20%?40%. In every city except St. Louis, a maximum in warnings is located 5?15 km to the east (downwind) of the city center. Additional analysis reveals that the location of the warning maxima often varies with wind direction. Areas of enhanced convective activity are also evident in and around each city. Many of these areas are found to the east of the city center and are coincident with areas of increased warnings. This alignment could suggest that urban influences are creating areas of enhanced severe weather potential on the eastern side of large cities. However, there are also instances where the locations of maxima in warnings, local storm reports, and convective activity are spatially offset. In these locations, it is possible that other factors are impacting the distribution of one or more of these fields.