Polar Vortex:

The Polar Vortex is a persistent cyclone which happens in the air above the night-time pole. As autumn moves into winter, the polar air begins to cool, descend, and veer east; spinning up the cyclone. The boundary of the cyclone is known as the Jet Stream.  The Jet Stream is a flow of fast moving air (high winds) located near the tropopause and plays a very large role in our weather by moving storm systems around the planet. The tropopause is a region of the atmosphere located approximately 10 km from the ground which divides the troposphere (layer of air we live in) from the stratosphere (the region of air above us which contains ozone).

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