New York City

Nuns celebrate as they wait for the arrival of Pope Francis at St Patrick's Cathedral in New York yesterday

  © enzo Pinto/AFP

Nuns celebrate as they wait for the arrival of Pope Francis at St Patrick’s Cathedral in New York yesterday

Polar Vortex Weather System Brings Artic Temperatures Across Wide Swath Of U.S....NEW YORK, NY - JANUARY 07:  Commuters walk through Manhattan's Grand Central train terminal on January 7, 2014 in New York City. A 'polar vortex'  of frigid air centered on the North Pole dropped temperatures to a record low 4 degrees in New York City.

John Moore/Getty

Commuters find refuge in Manhattan’s Grand Central train terminal as temperatures drop below freezing in New York city.