"It's like a potpourri of things that can create tornadic environments," he said.
Kelsey Ellis, a professor at the University of Tennessee in Knoxville and an expert on hazardous weather climatology, said it's important to understand what it takes to form a tornado to get a clearer picture of what's happening in Tennessee.
Instability, or air that wants to rise, is a key ingredient to form a strong thunderstorm and possible tornado.
"If you're standing near a strong thunderstorm, you may feel warm air at your back flowing into and feeding the storm," Ellis said. "Greater instability helps make that happen."