The US north-east is preparing to be hit by the "catastrophic" ice storm that has already caused chaos across the usually mild south, with 13 deaths being blamed on the treacherous weather.
The deadly storm crippled travel and cut put power to thousands of households in the US. More than 350,000 people are reportedly still without power.
Ice combined with wind gusts up to 30mph snapped tree branches and power lines. More than 200,000 homes and businesses lost electricity in Georgia, 130,000 in South Carolina and nearly 30,000 in Louisiana.
Washington DC awoke to its heaviest snowfall this winter. The federal government was closed, along with school districts in the area.
Washington's bus service was suspended, and residents were advised to stay home if possible rather than risk a commute through snow accumulations of as much as a foot throughout the area.
Schools in New York remained open and the city's Sanitation Department called on reinforcement crews to help shovel out sidewalks, fire hydrants and other snow-blocked areas.
In Connecticut, Governor Dannel Malloy ordered non-essential workers to stay home on Thursday.
Residents in North Carolina and Virginia have been preparing for up to one foot of snow.
The National Weather Service (NWS) has warned a band stretching from north-eastern Pennsylvania through New York State's Hudson Valley and into New England could see 10 inches of snow.
In a warning issued on Wednesday, the NWS described the storm across the south as "catastrophic, crippling and paralyzing".
Winter storm warnings and advisories were in place from Arkansas east to much of the Atlantic coast, the NWS added. The storm is expected to hit northeastern US within the next two days with up to 15 inches of snow.
"We definitely consider this to be a high-impact event, and we're definitely telling everyone to stay off the roads and stay inside as much as possible," said Carl Barnes, a weather service forecaster in Sterling, Virginia.
At least 12 deaths across 22 states from Texas to Maine were blamed on the weather conditions including three people who were killed when an ambulance careered off an icy Texas road and burst into flames.
Over 5,000 airline flights across the US were cancelled and forecasters warned of more than an inch of ice possible in places.
Forecasters described the storm in Atlanta as one of the worst to strike the city since 1973, but did not cause as much disruption as the 28 January storm, which many were unprepared for.
President Barack Obama declared a disaster in South Carolina and for parts of Georgia and the Federal Emergency Management Agency said it was moving supplies to an emergency centre in Atlanta on Wednesday evening.
Additional reporting by Agencies