Outside-13, but expose thousands in metro NY

Outside it is freezing, but in the New York subway, the night was left with bare legs.

As the mercury dropped to 13 degrees below zero, thousands of New Yorkers dived into the subways in their underpants, often in combination with a thick winter coat. The New York happening is now copied in hundreds of other world cities. A comic art movement introduced the day in 2002.

The east coast of the US has been plagued for days by extreme cold and heavy snowfall.