 The polar vortex is an area of swirling cold air located over the Arctic. Although the polar vortex is around all year long, we pay attention when it comes further south, knocking on our door, making winter even colder. But how does it get here? Warming temperatures in the Arctic cause the polar jet stream to wander off course, causing the polar vortex to wobble and slip off the Arctic and over southern Canada and the United States, Europe and Asia. The increase of polar vortex events in these places is actually related to rising global temperatures and melting Arctic sea ice. Weird, right?