Extreme Heavy Rainfall and Flash Flooding August 3rd - August 10th, 2013
National Weather Service, Springfield, MO
Several rounds of showers and thunderstorms impacted southeastern Kansas and the Missouri Ozarks the first couple of weeks of August as a persistent upper pattern remained in place. An unusually strong upper trough of low pressure was located over the Hudson Bay area of Canada while an upper ridge of high pressure remained anchored across the southwest U.S. This resulted in a steady west to northwest flow aloft that brought a series of upper level disturbances across the region.
Meanwhile a front became nearly stationary and oscillated only slight to the north and south underneath the persistent west to northwest flow aloft. A flow of deep moisture from the Gulf of Mexico interacted with this boundary to aid the development of thunderstorms that trained along the boundary. The exceptionally moist atmosphere resulted in torrential rainfall rates.