Residents of the north-eastern US have been warned to stay indoors, as the region braces for a storm expected to dump up to 14in (35cm) of snow. Nearly 2,000 flights have been grounded nationwide as heavy snow fell from Illinois to Michigan in the US Midwest.
New York and New England are expected to see blizzard conditions, with wind gusts of up to 45mph (72 km/h). In Canada, temperatures of -26C (-14F) were recorded in Montreal and Winnipeg, not including the wind chill factor.
On Thursday, central Quebec recorded an actual temperature of -46C (-51F), Environment Canada meteorologist Bernard Duguay told the BBC.
Several inches of snow have already fallen in the US north-east, but the strongest part of the storm is expected on Thursday evening into Friday morning.