Watch: 'Life threatening' winter storm ravages Buffalo in United States, death toll rises to 31

Millions of people hunkered down in a deep freeze overnight and early morning on Sunday to ride out the frigid storm that has killed at least 20 people across the US, trapping some residents inside homes with heaping snow drifts and knocking out power to several hundred thousand homes and businesses.

The storm unleashed its full fury on Buffalo, with hurricane-force winds and snow causing whiteout conditions, paralysing emergency response efforts — New York Governor Kathy Hochul said almost every fire truck in the city was stranded — and shutting down the airport through Monday, according to officials.

The National Weather Service said the snow total at the Buffalo Niagara International Airport stood at 43 inches (109 centimeters) at 7am on Sunday.

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