Arctic blast

Parts of the US and Canada are braced for potentially record-breaking low temperatures as a blast of arctic air blows across North America.

The US National Weather Service said in a statement that the "coldest weather in years will be making its prescence known from the Upper Midwest to the Mid-Atlantic region for the beginning of the work week."

Temperatures in some parts could feel as low as –45°C with the effect of wind chill, forecasters say.

Thousands of flights have been cancelled, public schools ordered shut, some cities have banned driving, and residents are being urged to stay indoors for their own safety.

The storm and the deep cold have been blamed for 16 deaths in recent days.