More than 60 million Americans are under winter weather alerts as a huge winter storm is forecast to bring the heaviest snowfall and coldest temperatures in over a decade.
Much of Canada and 30 US states from Kansas to the East Coast are under weather alerts, the National Weather Service (NWS) said. Snowfall of 6-12in (15-30cm) is expected from Ohio to Washington DC.
A state of emergency has been declared in Kentucky, Virginia, West Virginia, Kansas, Arkansas and Missouri. Even parts of normally balmy Florida are expected to experience freezing conditions.
Severe travel delays are expected. Nearly 1,500 flights into and out of the US have been cancelled and nearly 5,000 more delayed, according to FlightAware.com.
Amtrak has also cancelled numerous train services.
American, Delta, Southwest and United airlines are waiving change fees for passengers because of the potential flight disruptions.
