Weather security

What's happening with the polar vortex this year?

Last January the polar vortex was about to plunge into the United States, unleashing an unforgiving and deadly outbreak of Arctic air across much of the nation -- which is why forecasters are keeping a close eye on what it may do as 2020 begins.

During the January 2019 polar vortex invasion, officials warned residents of nearly instantaneous frostbite danger as AccuWeather RealFeel® Temperatures plunged as low as minus 77 degrees Fahrenheit in the Upper Midwest. The punishing cold froze the Great Lakes, creating slushy waves as eerie sea fog blanketed parts of the region. The extreme weather forced the cancellation of thousands of flights at Chicago's O'Hare International Airport and school closures across portions of the Midwest and Northeast.

This year, the polar vortex, which is a large pool of frigid air - typically the coldest in the Northern Hemisphere - that often sits over the polar region during the winter, is forecast to remain strong and hover near the Arctic Circle in the coming weeks.