During the summer of 2012, a series of severe wind events associated with powerful thunderstorms, known as derechos, affected widespread areas of the United States. The first of these derechos occurred in late June, and caused power outages that affected nearly five million people. Three weaker derechos occurred in July, and a final derecho disrupted activities in Chicago, Illinois in early August. Only three tornadoes were reported in conjunction with the derechos.