sentences:  Some of the most notable weather events in the county include the 1965 Palm Sunday tornado outbreak, the Blizzard of 1967, the 1967 Belvidere - Oak Lawn tornado outbreak, the Blizzard of 1979, the Flood of 1996, the Blizzard of 1999, the Early Winter 2006 North American Storm Complex, the 2007 Midwest flooding event, the January 2008 tornado outbreak sequence, and the Blizzard of 2011.As of the 2010 census, there were 308,760 people, 109,199 households, and 82,288 families residing in the county.The population density was .