Deep freeze in North America

The coldest, most dangerous blast of polar air in decades gripped the US Midwest and pushed toward the East and South and eastern Canada.

Ice in the Mississippi River flows past the Gateway Arch in St, Louis. As Missourians muddled through another frigid day Tuesday, the worst cold snap in nearly two decades was about to come to an end but many roads remained partly snow-covered two days after a winter storm dumped several inches of snow.

Photo credit: AP

The Chicago skyline is seen behind a large chunk of ice near North Avenue Beach as cold temperatures remain with wind chills nearing minus 30 Fahrenheit in Chicago.

Photo credit: AP

The lighthouse at Pere Marquette Beach is completely frozen after a severe winter storm hit in Muskegon, Michigan.

Photo credit: AP

Steam rises from downtown buildings as temperature begin to climb above zero for the first time in more than 30 hours in Chicago, Illinois.

Photo credit: AFP

A tug boat navigates the frozen Mississippi River in St Louis.

Photo credit: AP

Ice covers rocks and brush on the break wall at Edgewater Park in Cleveland. An official low of -11 degrees broke the 130-year-old record for the date as cold polar air spread from the Midwest to southern and eastern parts of the U.S. and eastern Canada.

Photo credit: AP

A man walks past a snow encrusted bicycle with wind chills nearing minus 30 Fahrenheit in downtown Chicago.

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A woman jogs along the Charles River on a foggy winter morning in Cambridge, Massachusetts.

Photo credit: Reuters

Ice builds up along Lake Michigan at North Avenue Beach as temperatures dipped well below zero on January 6, 2014 in Chicago.

Photo credit: AFP

People go sledding following a snow storm in Prospect Park on January 4, 2014 in the Brooklyn borough of New York City. The major winter snowstorm named 'Hercules', forced New York City public schools to close, cancelled hundreds of flights at airports and shut down the Long Island Expressway, is now bringing below freezing temperatures to the Midwest and mid-Atlantic and to the Northeast.

People enjoy a new ice rink at the Samuel J. and Ethel LeFrak Center following a snow storm in Prospect Park on January 4, 2014 in the Brooklyn borough of New York City.

In this image, ice builds up along Lake Michigan at North Avenue Beach as temperatures dipped well below zero on January 6, 2014 in Chicago, Illinois. Chicago hit a record low of -16 degree Fahrenheit on January 7 morning as a polar air mass brought the coldest temperatures in about two decades into the city.

Ray Pass gets a chance to use his cross country skis on a street in University City near his home on January 5, 2014. Pass, who is originally from New York, said this snow is "nothing" compared to snows back east.

Ice from breaking waves coats a house along the shore in Scituate, Massachusetts on January 3, 2014. The winter storm slammed into the US northeast with howling winds and frigid cold, dumping nearly 2 feet (60 centimetres) of snow in some parts and whipping up blizzard-like conditions.

A man walks in the snow down a road along the shore in Scituate, Massachusetts on January 3, 2014.

A man and his dog contend with blowing snow in Brooklyn following a snow storm that left up to 8 inches of snow on January 3, 2014 in New York.

Winds whip snow from the beach across Winthrop Shore Drive on January 2, 2014 in Winthrop, Massachusetts.

A man plows snow during winter storm 'Hercules' in lower Manhattan on January 2, 2014 in New York City.

Icicles on a window are seen in front of airplanes during a winter snow storm in Boston, Massachusetts on January 2, 2014.

A worker removes slush from the plaza as light snow falls at the US Capitol in Washington on December 10, 2013.

Jim Ridley uses a flashlight to get his mail on December 26, 2013, in Litchfield, Maine.

Karen Gibbs walks through a labyrinth of icy broken trees and downed power lines to her home on Maplehurst Drive in Belgrade, Maine on December 26, 2013.