The polar vortex is about to split again, and it could bring a 'big' winter storm by MLK Day.

"I do expect that eventually winter weather will become more active across the U.S. post-MLK Day" on Jan. 18

https://www.usatoday.com/story/news/nation/2021/01/11/polar-vortex-split-winter-weather-coming-eastern-central-us/6623574002/