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US temperatures set to plummet to record lows

Parts of America and Canada are experiencing near record-breaking low temperatures from a severe winter storm that has claimed at least 16 lives.

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What is the 'Polar Vortex' affecting the United States?

The Polar Vortex is described as a cyclone near one or both of the earth's poles. Credit: NOAA

The US National Weather Service has produced a graphic explaining the 'polar vortex' which has brought record low temperatures to many parts of the United States.

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