The April 20, 2004, tornado outbreak was a tornado outbreak that affected parts of the U.S. Upper Midwest on April 20, 2004. Thirty tornadoes formed in eastern Iowa, extending into northern and central Illinois and Indiana. A tornado that struck Utica, Illinois, was the only one to cause fatalities. An unusual feature of the outbreak is the fact that it was largely unexpected, as the SPC only issued a "See Text" outlook area the day of the event.