Could an early polar vortex disruption change Chicago's winter forecast? What to expect

Some forecast models are pointing to an unusually early disruption of the polar vortex that could influence weather patterns across the Northern Hemisphere. The polar vortex is a large circulation of very cold air high above the Arctic, extending through the stratosphere. Meteorologists commonly monitor it around 100,000 feet above Earth s surface. Sometimes atmospheric disturbances cause that circulation to weaken, stretch or even split apart. This can be accompanied by a dramatic rise in temperatures high above the Arctic, known as a sudden stratospheric warming event. What s especially unusual about the current forecast is the timing. These events typically occur during the middle of winter, not early November. The National Oceanic and Atmospheric Administration has acknowledged the potential for an unusually early warming event. If it meets the criteria for a major SSW, it could be the earliest documented on record, going back to the late 1950s. The earliest widely reco