The polar vortex is a low-pressure system of cold air that swirls above both of Earth’s poles. Over the North Pole, the wind flows counterclockwise in the stratosphere around 16 to 50 kilometers ...

A sudden stratospheric warming event reversed the winds that make up the northern polar vortex on March 9. A new animation shows the vortex also moved away from the Arctic towards Europe.

The upcoming event will mark the second major disruption of the Polar Vortex this year. A collapse in mid-February coincided with a strong cold air release across much of the central and eastern ...