US winter storm warning: Why more than 200 million people are under snow, ice and cold alerts
A slow-moving winter storm is set to impact more than half the US, bringing heavy snow, widespread ice, extreme cold and risks of prolonged power outages.
A slow-moving winter storm is set to impact more than half the US, bringing heavy snow, widespread ice, extreme cold and risks of prolonged power outages.
The polar vortex death toll was at least 21 at last count