For the past several months, an El Niño of “ super ,” “ mega ,” and “ monster ” proportions has been making headlines. Climate scientists say this event will likely lead to an overall mild winter for the U.S., but a look at the polar vortex reminds us that El Niño won’t be the only factor shaping the season.

Forecast models show that the polar vortex could undergo an “unprecedentedly” early large disruption in the first weeks of November, according to Judah Cohen, a climatologist at the Massachusetts Institute of Technology and a leading expert on this phenomenon. He tracks the polar vortex and issues forecasts via his blog, and his latest outlook suggests it could soon make history.

“This level of polar vortex disruption is most common in January and February,” Cohen told Gizmodo in an email.…