Polar Vortex Wobble May Bring Arctic Blast to Northern US Around Thanksgiving

According to the latest weather forecasts as of mid-November 2025, the northern US, including Wisconsin, could be in for a return of Arctic air around the Thanksgiving holiday. Meteorologists are closely monitoring a potential "wobble" in the polar vortex, a swirling mass of frigid air high in the atmosphere, which could push bitterly cold temperatures into the region.

This development comes after a recent winter storm brought over 10 inches of snow to parts of Wisconsin. While the upcoming Arctic blast is unlikely to be as intense as that previous system, it could still lead to subfreezing wind chills and an increased risk of lake-effect snow over the Great Lakes.

Factors contributing to the volatile winter weather include a weakening polar vortex and the ongoing La Niña pattern in the Pacific Ocean. Forecasters note that when the polar vortex is unusually weak, it becomes more prone to "wobbling" and sending Arctic air southward. Meanwhile, La Niña can influence the jet stream, affecting where cold outbreaks occur and how long they linger.

Residents of the northern US, especially those in the Great Lakes region, should prepare for a potential shift to much colder temperatures and the possibility of lake-effect snow around the Thanksgiving holiday and into early December.