American Airlines Group Inc. canceled hundreds of flights early Saturday as an icy winter storm struck southeast U.S. cities. The National Weather Service warned of hazardous conditions in areas including Atlanta, Delta’s largest hub, and Charlotte, North Carolina, an American hub. As ice and snow piled up, more than 385 flights were canceled at Hartsfield-Jackson Atlanta International Airport and more than 164 at Charlotte Douglas International Airport, according to flight-tracking website American has already canceled more than 850 flights due to the storm, the airline said, as well as 50 flights scheduled for Sunday.