Parts of the US and Canada are gripped by freezing temperatures as a “polar vortex” weather system sends the mercury running for cover.

The latest freeze follows a snow storm, which has already blanketed areas of Canada and north-eastern United States.

The weather has played havoc with transport with 3,000 flights cancelled on Monday on top of the thousands that failed to take off over the weekend.

Schools have closed in a number of states and residents are being advised to stay indoors.

Sports fans are a hardy lot and in Wisconsin the 70,000 people who braved the conditions to see the Green Bay Packers play the San Francisco 49ers dressed for the occasion.

“Four layers of long johns, two sets of snow pants, four shirts, a sweatshirt, and a coat,” said one wrapped up Packer.

Green Bay offered fans free hand warmers, hot coffee and chocolate.

Sadly on the field they could not deliver a result losing by a chilling 23 to 20 to the boys from California.