In Pictures

Extreme cold blasts North America

Dangerously cold temperatures grip much of Canada and the USA.

A blast of cold air from the Arctic has plunged across much of Canada and the USA.

7 Jan 2014

Much of North America is in the grip of extremely low temperatures.

Cold air has rushed in from the Arctic, after a high pressure over northeast Canada and Greenland blocked the usual track of the weather.

At this time of year the Arctic sees 24 hours of darkness, and cold air festers over the region.

Strong winds circulate around the pole, trapping the cold air in place and creating what’s known as a ‘polar vortex’ a swirling mass of cold air, which rotates anti-clockwise around the Arctic.

This year, the usual path of polar vortex has been disrupted, sending a blast of cold air into North America.

Weather this severe hasn’t been seen in the region since 1994.

Residents are being urged to stay indoors, with meteorologists warning that temperatures this low can be life-threatening, and severe frost bite can set in within ten minutes.

Many locations have shivered in their coldest weather since 1994.

The temperature in Chicago at midday local time on Monday was an eye-watering -26C, but the wind made it feel far colder than that.

The strong winds, blowing at 32kph, ensured the temperature in Chicago felt more like -40C.

In temperatures this low, severe frost bite can set in within ten minutes.

So far the lowest wind chill temperature that has been recorded was -53C in Comertown, Montana.

The cold weather has forced the closure of many schools throughout the region, and prompted authorities to urge residents to stay indoors.

Thousands of flights were cancelled across North America, including 2,000 from Chicago.

29cm of snow fell in Indianapolis, Indiana, on Sunday. This is the second heaviest snowfall recorded in a day in the city.

More heavy snow is expected on Tuesday to the south of the Great Lakes, where there could be 1.5 metres of snow.

The cold snap is expected to gradually ease over the next few days and by Friday temperatures in Chicago should finally creep above freezing.