Huge winter storm hits US, 7 states declare state of emergency

More than 60 million Americans across more than 30 states are in the grips of a huge winter storm that could bring the heaviest snowfall and coldest temperatures in over a decade, BBC reports.

A polar vortex has brought frigid weather down from the Arctic to the central US, with extreme weather conditions accompanying it.

Thousands of flights are delayed or cancelled, many roads cut and schools shut as a result of the storm.

Blizzards are expected to bring whiteout conditions to Kansas and Missouri, where a state of emergency has been declared.

A state of emergency has also been declared in the states of Kentucky, Virginia, West Virginia, Arkansas and parts of New Jersey.

The weather is expected to begin easing on Monday.