Among the cities at greatest risk for severe weather are Chicago; Columbus, Ohio; Fort Wayne, Ind.; Aurora, Ill.; Dayton, Ohio, and Louisville, Ky., Accuweather.com said.
Accuweather.com meteorologists compared the potential storm to a "derecho," a widespread and long-lived wind storm associated with a band of rapidly moving showers or thunderstorms, with wind speeds between 70 and 80 mph typically observed.
Thunderstorms are expected Wednesday evening along a corridor crossing east-central Iowa and northern Illinois, with potential heavy flooding as the storm moves through Detroit, Cleveland and Pittsburgh.
Celebrity Families of 2014 [PHOTOS]