PHILADELPHIA — Yet another storm paralyzed much of the East with heavy snow and sleet Thursday, giving the winter-weary that oh-no-not-again feeling, while hundreds of thousands across the ice-encrusted South waited in the cold for the electricity to come back on.

At least 20 deaths were blamed on the treacherous weather, including that of a pregnant woman who was struck and killed by a mini-snowplow in a New York City parking lot as she loaded groceries into her car.

The sloppy mix of snow and face-stinging sleet grounded more than 6,500 flights Thursday and closed schools and businesses as it made its way up the heavily populated Interstate 95 corridor, where shoveling out has become a weekly — sometimes twice-weekly — chore.

“Snow has become a four-letter word,” lamented Tom McGarrigle, a politician in suburban Philadelphia.

In its icy wake, utility crews in the South toiled to restore electricity to more than 800,000 homes and businesses, mostly in the Carolinas and Georgia. Temperatures in the hard-hit Atlanta area, with more than 200,000 outages, were expected to drop below freezing again overnight.

Baltimore awoke to 15 inches of snow. Washington, D.C., had at least 8, and federal offices and the city’s two main airports were closed. The Virginia-West Virginia state line got more than a foot.

Philadelphia had nearly 9 inches, its fourth 6-inch snowstorm of the season — the first time that has happened in the city since record-keeping began in the late 1800s. New York City received nearly 10 inches, and parts of New Jersey had over 11.

In some places, the snow and freezing rain eased up during the day, but a second wave was expected overnight into Friday.

“It’s like a dog chasing its tail all day,” said Pat O’Pake, a plow operator in Pennsylvania.

In New Cumberland, Pa., which had about 10 inches of snow by midafternoon, Randal DeIvernois had to shovel after his snow blower conked out.

“Every time it snows, it’s like, oh, not again,” he said. “I didn’t get this much snow when I lived in Colorado. It’s warmer at the Olympics than it is here. That’s ridiculous.”

In New York, Min Lin, 36, died after she was struck by a utility vehicle with a snowplow attached to it as it backed up outside a shopping center in Brooklyn. Her nearly full-term baby was delivered in critical condition via cesarean section.

No immediate charges were brought against the snowplow operator.

Across the South, the storm left ice-encrusted trees and driveways and snapped branches and power lines.

In Bonneau, S.C., Jimmy Ward and his wife, Cherie, lost power and spent Wednesday night in their home, warming themselves in front of a gas log fire.

But after running low on propane, they headed Thursday night for a hotel, where it was expected to be cozier but a lot less exciting.

“From 2 o’clock yesterday until this morning, it just sounded like gunfire — all the trees popping and falling,” Cherie Ward said.

In North Carolina, where the storm caused huge traffic jams in the Raleigh area on Wednesday as people left work and rushed to get home in the middle of the day, National Guardsmen in high-riding Humvees patrolled the snowy roads, looking for any stranded motorists.