In pictures: Polar vortex freezes Midwest, parts of US with cold air

 A bone-chilling polar vortex has plunged the Midwest, stretching from the Dakotas through Maine, into a wave of dangerously cold Arctic air.

Snow fall in the country is expected from as far as south in Alabama and Georgia. The midwest remained the most affected region as temperatures dipped to below -18 degrees Celsius.

By nightfall the mercury was hovering at -14C in Detroit and -29C in Minneapolis.

Photos from AFP and Reuters showed the prevailing state of the country during the hard-hitting weather.