"This storm is dangerous," said North Carolina Governor Pat McCrory. "Road conditions are treacherous in many areas."
Massive traffic jams from snow slicked roads made evening commutes in the South agonizing, hours-long affairs with the usually temperate cities of Raleigh and Charlotte transformed into ice- and snow-covered parking lots.
Hundreds of traffic accidents were reported in the Carolinas and Georgia, where frozen roads hampered emergency response efforts.
President Barack Obama has declared states of emergency in Georgia and South Carolina in order to deploy federal resources to help deal with the frigid storm.
McCrory urged North Carolinians to stay indoors -- even if it meant sleeping at work -- rather than risk the treacherous roads.
"If you're in a safe warm place, stay in a safe warm place," McCrory told CNN.
"We've already had two fatalities and we don't want to see more."
Specialty website FlightAware said airlines canceled at least 3,700 flights on Wednesday while a further 6,500 had been scrapped on Thursday, including many to and from New York, Atlanta, Philadelphia and Washington.
Downtown Washington was a virtual ghost town. Most buses were not running and subway cars were nearly empty.
As the snow started blowing in overnight, temperatures hovered around 26 degrees Fahrenheit (minus three Centigrade) but the bracing winds making it feel more like 15 degrees, forecasters said.
The White House cancelled its daily news briefing, and federal agencies told workers to stay home.
The Federal Emergency Management Agency said it was in contact with state emergency offices in densely populated Maryland, Pennsylvania and Virginia to assess their assistance needs as the storm builds.
In addition to the FEMA aid, various localities across the region had readied emergency shelters at churches and recreation centers where residents could stay warm should they lose power.
Military personnel had also been mobilized, with more than 2,300 Army and Air National Guard pressed into action, according to a Pentagon statement.