Severe weather devastated homes, overturned cars and felled trees, with the National Weather Service confirming at least four tornadoes in Texas.
The mayor of Canton, Texas - a city some 60 miles (95 kilometers) east of Dallas - said the death toll there stood at four.
"It is heartbreaking and upsetting to say the least," Mayor Lou Ann Everett told journalists Sunday.
A spokeswoman for the Arkansas Department of Emergency Management told AFP severe weather had caused at least five fatalities in that state.
The Mississippi Emergency Management Agency had confirmed two deaths, one of them a child who was killed by electric shock in floodwater.
Heavy rains also lashed the midwestern state of Missouri, with at least two reported casualties. According to CNN one of those killed was a 72-year-old woman who was stranded in her car as it was swept away by floodwaters.
Cars and trucks are damaged as the walls blew out of the I-20 Dodge dealership after a tornado hit near Canton, Texas, Saturday, April 29, 2017. (AAP) Source: AAP
In Tennessee, a two-year-old girl was pronounced dead at a hospital in Nashville after she was struck by a heavy metal soccer goal blown over by heavy winds, according to the city's police department.
As of late Sunday the NWS was projecting major flooding to continue in parts of eastern Oklahoma, northern Arkansas, Missouri, Illinois and Indiana.
Authorities warned that severe storms potentially packing heavy winds, large hail and tornadoes could hit parts of the mid-Atlantic and northeastern US by Monday afternoon.
