(Image source from: U.S experiencing the coldest weather in 20 years})

For the frost-bound U.S. that is already battling deep-freeze weather, last Monday was the worst of all, with the first day of the week registering the coldest temperature in the last two decades. More than half of the U.S. fell under the grips of 'polar vortex', a whirlpool of ice-cold, thick air that gravitated yesterday morning, flogging parts of the country and grounding more than 4,400 flights.

Chicago registered a record low temperature of minus 16 degrees on Monday, the previous record being minus 14 set in 1988.

Following the frigid temperatures, many public schools were closed down across Minnesota, Chicago, Milwaukee and St Louis.

With wind chill warnings stretching from Montana to Alabama the deep freeze is expected to continue until Tuesday.

Nearly 187 million people, which is more than half of the U.S. population, were under a wind chill warning on Monday.

Image Source: Daily Mail

AW: Suchorita Dutta Choudhury