Several US states declare emergencies as millions hit by huge winter storm | BBC News

More than 60 million Americans are in the grips of a huge winter storm that could bring the heaviest snowfall and coldest temperatures in over a decade. A state of emergency has been declared in seven states - Kansas, one of the worst-hit areas, Missouri, Kentucky, Virginia, West Virginia, Arkansas and parts of New Jersey. Forecasters say the extreme weather is caused by a polar vortex - an area of cold air that circulates around the Arctic - bringing cold weather to the central US. Thousands of flights have already been delayed or cancelled, with many roads cut off and schools shut as a result of the storm. Subscribe here: http://bit.ly/1rbfUog For more news, analysis and features visit: www.bbc.com/news #US #Snow #BBCNews