US to shiver in ‘once-in-a-generation’ polar vortex

The US will shiver this week in a once-in-a-generation deep freeze, forecasters warn.

The most extreme arctic blasts, caused by a spinning pool of cold air known as the polar vortex, could bring temperatures as low as -53C.

Read more: https://www.bbc.com/news/world-us-canada-47047089