US braces for record lows in big freeze

Authorities urged Americans to stay indoors and stock up on food after a fierce winter storm killed 11 people and forecasters said the Arctic blast could bring record low temperatures.
There was no sign of respite Saturday from the brutal chill that has struck since the start of 2014 in parts of the northeastern United States and Canada, prompting New York and New Jersey to declare a state of emergency.
Following heavy snowfall Thursday, one of the coldest Arctic outbreaks in the past two decades is set to plunge America's Midwest close to record cold conditions.
Chicago could today see some of its most bracing weather ever, with temperatures hovering around minus 10 degrees Fahrenheit (minus 23 Celsius), weather analysts said.
Gusty winds could bring what forecasters at the National Weather Service called "very dangerous levels" of wind chill.
"Incredibly, it may feel as cold as -50 to -60 (Fahrenheit) on Sunday night over sections of the north-central states with the frigid air remaining in place into early next week," it said.
In such conditions, exposed skin would suffer frostbite in as little as five minutes, forecasters cautioned.
Authorities have urged people in the worst-hit areas to spend the first weekend of the new year at home for their own safety and to allow rescue and clean-up teams to get to work as quickly as possible.