Blizzards are battering the U.S. from coast to coast, triggering devastating flight cancellations and delays on the biggest travel holiday of the year – as 50 million people across the country are placed under a winter weather alert. Two winter storms swirling over the country have already claimed three lives. Two children were found dead and another was missing in Arizona on Saturday after a car they were in got stuck while crossing a storm-swollen creek outside Phoenix. A 37-year-old man was killed in a car accident near Cavour, South Dakota early Friday morning after the pickup truck he was in lost control on the icy road, fell into a ditch and rolled over. This week snow, icy, freezing rain and gust winds are forecast to blow the West Coast and the Northeast, hitting Chicago, Philadelphia, Boston and New York hard.