"Numerous significant tornadoes, some of which should be long-track and potentially ... One pileup involved an estimated 38 cars. "It's the worst I've ever seen," Barkley said, calling the near-zero visibility a nightmare. "We couldn't tell that they ...

The National Weather Service issued multiple tornado and severe thunderstorm warnings early Saturday for areas in Alabama, Kentucky, Mississippi, Tennessee, Illinois, Indiana and Texas.

Deadly winter storms are expected to hit multiple parts of the U.S., and millions of Americans are bracing for tornadoes. NBC News' Adrienne Broaddus has more on what to expect and how to prepare.