Jolie Lee

USA TODAY Network

This week's "polar vortex" brought record-low temperatures across the country. The weather closed schools, canceled flights and even forced Chicago's resident polar bear to stay indoors at the zoo.

But was it cold enough for Niagara Falls to freeze over?

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Not quite. Despite appearances, Niagara Falls did not freeze over completely.

Certain sections of the waterfalls froze, but water is still flowing, said Angela Berti, spokeswoman for Niagara Falls State Park.

The waterfalls sometimes look like they are frozen over because ice builds up, she said.

The American Falls — Niagara Falls is comprised of waterfalls on both sides of the U.S.-Canadian border — have frozen over twice, in 1936 and 1938.

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