Las temperaturas han marcado récords en Estados Unidos y en Chicago, con el lago Michigan congelado, han llegado a los 50 grados bajo cero.
CHICAGO, IL - JANUARY 06: Mist rises from Lake Michigan as temperatures dipped well below zero on January 6, 2014 in Chicago, Illinois. Chicago hit a record low of -16 degree Fahrenheit this morning as a polar air mass brought the coldest temperatures in about two decades into the city. Scott Olson/Getty Images/AFP
CHICAGO, IL - JANUARY 07: Passengers heading into downtown wait on an "L" platform for the train to arrive in below zero temperatures on January 7, 2014 in Chicago, Illinois. Platforms were crowded and trains were delayed because doors on the trains kept freezing open. Chicago is experiencing its third consecutive day of below zero temperatures. Scott Olson/Getty Images/AFP