A derecho is a widespread, long-lived, straight-line wind storm normally associated with fast-moving severe thunderstorms known as a meso-scale convective system (MCS). On June 29, 2012 a derecho surged east-southeast from the Ohio Valley across the Mid-Atlantic region causing widespread wind damage resulting in the loss of 4,000,000 people without power. Yesterday a similarly intense derecho moved rapidly across the Midwest U.S. knocking out power to over 500,000 people.
According to REUTERS grain bins in dozens of counties were toppled by 100 mph winds. In Cedar Rapids, IA Cargill stated that facilities have no power and are shuttered. Archer Daniels Midland Co. corn processing facilities have no power and being inspected for damage.
The Derecho caused 772 wind damage reports across the Midwest U.S. Many wind speeds toppled 100 mph. The storm started early Monday and intensified by evening from Michigan to Indiana. The most damage reports were reported in Illinois.