How frigid polar vortex blasts are connected to global warming

How frigid polar vortex blasts are connected to global warming: A record-breaking cold wave is sending literal shivers down the spines of millions of Americans. Temperatures across the upper Midwest are forecast to fall an astonishing 50 degrees Fahrenheit (28 degrees Celsius) below normal this week – as low as 35 degrees below zero. Pile a gusty wind on top, and the air will feel like -60 F.