EF0 tornado in Pottawattamie County, Iowa

This was the second tornado that was observed by researchers tracking this storm. The tornado touched down briefly just northeast of exit 72 on Interstate 29 and lifted a little to the northeast, doing no apparent damage. The researchers were using DOW, a mobile radar system, and besides being visually seen by the researches, it also produced a tornadic signature on the DOW system.

A very strong and unseasonably cold upper level low pressure system that was tracking across the northern plains brought a strong low level jet to the region during the early morning hours of June 11th. The warm and unstable air that worked north into the region helped spawn early morning severe thunderstorms across eastern Nebraska and southwest Iowa. Later that day as the upper level system worked into the central Dakotas, a cold front pushed across the region. This helped set off another round of thunderstorms that developed over east central Nebraska by late afternoon.

Isolated small supercell thunderstorms initially developed ahead of the cold front over eastern Nebraska, but they were quickly overtaken by a broken line of larger supercell thunderstorms, some of the heavy precipitation type, that developed along the cold front. Cell mergers and training were observed well into the evening hours as the activity quickly spread across southwest Iowa. The storms produced a total of 8 confirmed tornadoes in the Omaha/Valley warning area which covers eastern Nebraska and southwest Iowa.