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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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Giant ice boulders found on Lake Michigan shore

Giant ice boulders have been formed along the shores of Lake Michigan, as freezing conditions in the US continues to impact the Midwest.

Footage of the ice boulders, which have formed in the freezing waters of Lake Michigan, was captured in Glen Arbor and shared on the town's local Facebook page.

The giant ice balls started as small chunks of ice, before growing layer by layer in sub zero water, with some locals claiming they are as big as 50cm in diameter.

The rare nationwide chill which has been caused by the so-called "polar vortex" - an Arctic low pressure system - is expected to keep a grip on much of the country for at least another day, with cutting winds and blizzards posing the most danger.

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