Arctic winter storm displaces overone million people in US.

Arctic winter storm has placed more than 135000000 people under weekend weather alerts ahead of the busiest travel days of the year.

The alerts stretch from coast to coast and reach as far south as the US-Mexico border and Florida, the Sunshine State.

Major airports have cancelled thousands of flights as the storm intensifies.

The cold snap could bring the iciest Christmas in decades, say forecasters.

The National Weather Service has warned that major areas, like the city of Des Moines, Iowa, frostbite will be in danger.