Reuters: A blast of Arctic air gripped the vast middle of the United States on Monday with the coldest temperatures in two decades causing at least four deaths, forcing businesses and schools to close and canceling thousands of flights.
Shelters for the homeless were overflowing due to the severe cold described by some meteorologists as the "polar vortex" and dubbed by media as the "polar pig."
Temperatures were 20 to 40 degrees Fahrenheit (11 to 22 degrees Celsius) below average in parts of Montana,...