Greensboro police officer A.R. Schoonmaker pushes a car, which became stuck on a hill Wednesday during the heavy snow in downtown Greensboro, N.C. The winter storm wreaked havoc in the South and is moving up the East Coast.

ATLANTA — Small armies of utility workers labored to turn the lights and the heat back on for hundreds of thousands of Southerners as a winter storm that left them without power threatened major cities further up the East Coast.

The Deep South remained a world of ice-laden trees and driveways early today after several unusual days of sleet and snow brought by a powerful system that could bring more than a foot of snow to such metropolises as Philadelphia, Washington and Boston.

At least 12 deaths across the South have been blamed on the stormy weather and nearly 3,300 flights nationwide were canceled with another day of complicated air and road travel ahead today, particularly in the Northeast.

Drivers in and around Raleigh, N.C., became snarled Wednesday in huge traffic jams and abandoned cars in scenes reminiscent of motorist woes in Atlanta during a storm two weeks earlier. In Atlanta, many streets were eerily quiet this storm, with drivers heeding dire warnings to stay off the roads. State troopers say they worked more than 200 crashes in Georgia. Snow was forecast to stop falling and temperatures to rise in most of the state by late morning, but ice remained a concern, with refreezing possible overnight and into Friday.

For some on slick, snow-covered interstates in North Carolina, commutes that should take minutes lasted hours after many got on the highways just as soon as snow and sleet began at midday.

And in South Carolina, more accustomed to occasional hurricanes, some could only relate the damage from ice-snapped tree limbs to that of bygone Hurricane Hugo. Even normally balmy Myrtle Beach, where millions of visitors cavort each summer, cars were coated in thick ice that also frosted palm trees and kiddie rides by the shore.

“I hate driving on this,” grumbled South Carolina resident Mindy Taylor, 43, on her way for rock salt, kitty litter or anything else to melt the ice. “Hopefully it’ll warm up by the weekend and it will all melt. I’m ready for Spring.”

In Alabama, forecasters gleefully spoke of weekend temperatures reaching the 60s after inches of snow or sleet in its northern parts.

The snow, sleet and freezing rain that iced Southern highways also knocked out electricity to more than half a million homes and business as it advanced today up the Interstate 95 corridor to the winter-weary mid-Atlantic states.

Some Southerners who two weeks ago reveled in the so-called “snow jam” sounded tired this time of sleet and ice encasing highways, trees and even the tombstones of a cemetery replete with Confederate graves.