In pictures: US 'big freeze'
- Published

Millions of people across the US are bracing themselves for bitter Arctic blast that could send temperatures plummeting to their lowest in decades.

Temperatures in the north and central US could feel as low as -60F (-51C) with the effect of wind chill from the rare "polar vortex", forecasters say.

The National Weather Service has warned that it is a "life-threatening wind chill".

The authorities are warning residents to remain indoors, both for their own safety and to keep roads clear for snow removal.

Over the weekend, the winter storm led to the cancellation of more than 3,700 flights.

Schools will also be closed across the state of Minnesota on Monday, as well as in parts of Wisconsin, Illinois and Indiana amongst others.
- Published6 January 2014