TROUSDALE CO., Tenn. (WKRN) — After powerful storms rocked Middle Tennessee, the National Weather Service Office in Nashville sent teams out to survey the damage. They confirmed that 6 tornadoes touched down Monday morning.

Lead forecaster Sam Shamburger said that severe weather is atypical for this time of year.

“Seeing them anytime in the month of December is unusual. And seeing multiple ones in one day is very unusual. A lot of this can probably be attributed to the La Niña pattern we’re in,” said Shamburger.

December is the second least likely month for tornadoes in Middle Tennessee, with September being the month with the fewest tornadoes historically.

La Niña Winters are often warmer and wetter, making severe weather more likely.

“We could see even more of these severe weather-type systems even during the winter months, December, January, February,” said Shamburger. “Stay alert over the next few months because it’s definitely possible that we could have more severe storms.”

Shamburger also says that determining whether the damage is from a tornado or straight-line winds can be challenging.

“Straightline winds can be just as damaging as weak tornadoes. In a lot of cases, it can be hard to determine what caused what,” said Shamburger. “So, one of the things we look for is in tornadoes is the damage is what we call convergent, and the damage goes inward toward the center. Whereas in straight-line winds a lot of times, a lot of the damage is in a straight line or even outward in a starburst pattern. So it’s kind of the opposite of a tornado. So we look for either what we call convergent or divergent damage.”