Residents in the Midwest are bracing for a 'flash freeze' set to send temperatures plummeting as low as -35 degrees Fahrenheit (-37 Celsius). The severe cold snap will be caused by a polar vortex pushing arctic winds down into the US, where all 50 states - even Hawaii - are expected to experience below freezing temperatures next Monday. More than 212 million Americans will affected by the bitterly cold conditions, CNN reports. However, the icy weather will be at its most extreme in the Midwest, where preparations are already in place to close schools and roads for fear of fatalities....