Missouri River Basin Tributary Runoff March 13-15, 2019
A bombogenesis (or bomb cyclone) storm dumped up to 2.25 inches of warm rainfall on frozen soils, and a heavy, wet snowpack over much of northern Kansas, eastern Nebraska, western Iowa, and southeastern South Dakota from Tuesday, March 12 through Thursday, March 14. The rapidly melted snowpack had a liquid water content ranging from 2-4 inches in Nebraska and Iowa and higher amounts into South Dakota. The combination of rain and melting snow on frozen ground resulted in minimal infiltration and record runoff. Enormous inflows from this flood event came from every major tributary that enters the Missouri River from Niobrara, Nebraska to the confluence of the Platte and Missouri Rivers. The Niobrara River quickly filled the very limited flood storage capacity at Gavins Point Dam forcing increased releases out of the dam. Missouri River flood levels dramatically increased south of Omaha due to the record flows in the Platte River. The combined flows of the Platte and Missouri Rivers greatly exceeded the capacity of several levee systems.