The storm morphology of deadly flooding events in the United States

This study investigates the synoptic and mesoscale environments associated with deadly flooding events in the United States from 1996 to 2005. A manual environment classification scheme, which includes analyses of surface charts, 500 hPa maps, and composite radar data (where available), is utilized to ascertain the primary ascent mechanisms and storm types producing these fatal flood events. Of the ten classifications in the scheme, the two most dominant ascent mechanisms associated with deadly floods include frontal boundaries (45%) and tropical systems (22%). Findings illustrate that mesoscale convective systems were responsible for 36% of the total number of flood fatalities over the period. The ten classifications are spatially and temporally analysed in order to assess region-specific risks associated with deadly flooding events. Copyright (C) 2007 Royal Meteorological Society.