Seven states declare states of emergency as flights are cancelled, schools closed and drivers face treacherous road conditions

The appeals for people to stay inside come amid forecasts of bone-chilling temperatures.

Associated Press reports that the eastern two-thirds of the US will experience dangerous cold and wind chills with forecasters saying temperatures could be well below normal.

In Chicago, temperatures hovered on Sunday as low as -10C and dropped to -11C in International Falls, Minnesota, on the Canadian border.