The Corn Belt derecho was a derecho which affected a large area of the central United States on June 29, 1998. In the morning, a supercell developed over eastern Nebraska and tracked into central Iowa. As the thunderstorm reached central Iowa, a strong rear-inflow jet developed which caused the thunderstorm to take on a different characteristic, becoming a derecho .
Over the Davenport, Iowa area of responsibility, numerous reports of wind gusts ranging from 80 to 100 mph were received. The highest measured wind gust of 123 miles per hour (198 km/h) mph was reported in Washington, Iowa near coordinates 41.3°N 91.7°W / 41.3; -91.7. This is the highest unofficial recorded wind gust in the history of the state of Iowa.
Along with the long-lived derecho, 28 tornadoes were reported, one an F2 which injured 85 people in central Iowa. Over eight states, the derecho and associated tornadoes killed one person and injured 174.