(UNI) At least 21 people have died in one of the worst cold snaps to hit the US Midwest in decades.
The temperature reached -17C (0F).
Some 250 million Americans overall have experienced the “polar vortex” conditions, a report in BBC said.
Hospitals have been treating patients reporting frostbite as parts of the country ground to a halt.
Temperatures are expected to swing to above average over the weekend.
The polar vortex descended on the United States on Tuesday, freezing much of the Midwest and New England region and affecting over 50 million people.
