Compléter 2_4vortexVersion en ligne 2_4vortex par John E 1 state travel and closed eight the icy to River a than dangerous This many part Shoveling It is colder Antarctica in many parts of USA . This is because of polar vortex - freezing air wind from the Arctic . rarely happens . There is a of emergency in towns . Schools and businesses have . People were told not to . They were told not go outside or breathe the air . The temperature in a of Minnesota fell to - 60º Celsius . The Chicago and Niagara Falls turned to ice . The cold killed people . Officials told people to go outside only if necessary . Freezing air can be for the skin . It can cause breathing problems . snow can also be dangerous .