Trevor Albert, right, Courtney Fulton, center, and Alejandro Escobar, all from Arlington, Va., run past the Lincoln Memorial in the snow in Washington, Thursday, Feb. 13, 2014. After pummeling wide swaths of the South, a winter storm dumped nearly a foot of snow in Washington as it marched Northeast and threatened more power outages, traffic headaches and widespread closures for millions of residents. (AP Photo/Charles Dharapak)
Workmen clear snow from the steps on Capitol Hill in Washington, Thursday, Feb. 13, 2014, as winter weather shut down Washington. After pummeling wide swaths of the South, a winter storm dumped nearly a foot of snow in Washington as it marched Northeast and threatened more power outages, traffic headaches and widespread closures for millions of residents. (AP Photo/J. Scott Applewhite)
Satellite view of a Nor'easter moving up the East Coast of the US on the morning of February 13, 2014.
NEW YORK, NY - FEBRUARY 13: A man braces his umbrella while walking through the snow on February 13, 2014 in New York City. Heavy snow and high winds made for a hard morning commute in the city. (Photo by John Moore/Getty Images)
A morning commuter walks in the plowed road as mixed winter precipitation falls Thursday, Feb. 13, 2014, in Philadelphia. Snow and sleet are falling on the East Coast, from North Carolina to New England, a day after sleet, snow and ice bombarded the Southeast. (AP Photo/Matt Rourke)
A man shields his face from a mixed winter precipitation Thursday, Feb. 13, 2014, in Philadelphia. Snow and sleet are falling on the East Coast, from North Carolina to New England, a day after sleet, snow and ice bombarded the Southeast. (AP Photo/Matt Rourke)
A worker plows snow from a parking lot during a major snowstorm February 13, 2014 in Manassas, Virginia. The biggest storm of the season dumped a thick snow blanket on the Washington, DC area overnight and early Thursday, shutting down the federal government, local schools, courts and government offices, airports and Metros bus service. AFP PHOTO / Karen BLEIER (Photo credit should read KAREN BLEIER/AFP/Getty Images)
A February 13, 2014 photo shows Massachusetts Avenue during rush hour, clear of traffic, in the northwest of Washington, DC on February 13, 2014. A major storm blowing in heavy snow and ice gripped large swaths of the winter-weary United States early Thursday, leaving a dozen people dead and knocking out power to hundreds of thousands of homes. AFP PHOTO/Mandel NGAN (Photo credit should read MANDEL NGAN/AFP/Getty Images)
A member of the Secret Service uniformed division keeps watch on a snow-covered Pennsylvania Avenue in front of the White House in Washington, DC on February 13, 2014. A major storm blowing in heavy snow and ice gripped large swaths of the winter-weary United States early Thursday, leaving a dozen people dead and knocking out power to hundreds of thousands of homes. AFP PHOTO/Mandel NGAN (Photo credit should read MANDEL NGAN/AFP/Getty Images)
Peace activist Taylor Hall clears snow from the peace vigil tent, which has been held outside the White House since 1981, during a snow storm in Lafayette Park across from the White House in Washington, Thursday, Feb. 13, 2014. After pummeling wide swaths of the South, a winter storm dumped nearly a foot of snow in Washington as it marched Northeast and threatened more power outages, traffic headaches and widespread closures for millions of residents. (AP Photo/Jacquelyn Martin)
CORRECTS STATE TO PENNSYLVANIA, NOT NEW JERSEY - Plows clear snow near Newtown, Pa., Thursday, Feb. 13, 2014. A winter storm dumped more than a foot of snow in parts of the Mid-Atlantic region as it marched Northeast and threatened more power outages, traffic headaches and widespread closures for millions of residents. (AP Photo/Mel Evans)
Snow covers the National Mall near the Washington Monument, center, in Washington, D.C., U.S., on Thursday, Feb. 14, 2014. The winter storm that cut electricity to more than half a million customers across the South and grounded 10,000 flights this week turned its power on the U.S. Northeast, bringing heavy snow from Virginia to Maine. Photographer: Andrew Harrer/Bloomberg via Getty Images
Cars of travelers are covered in deep snow February 13, 2014 at the long term parking lot at Dulles International Airport (IAD) in Virginia near Washington, DC. Ronald Reagan National Airport and Dulles International Airport were closed early Thursday with more than 300 flights cancelled at Reagan and over one hundred cancelled at Dulles. Specialty website FlightAware said airlines canceled at least 3,700 flights on February 12th and had already shelved 5,500 for Thursday, including many flights to and from New York, Atlanta, Philadelphia and Washington. The latest brutal freeze to hammer the eastern states of the country since the start of the year has been dubbed 'snowmaggedon,' 'mind-boggling' and 'historic' by major television networks and forecasters. AFP PHOTO/Paul J. Richards (Photo credit should read PAUL J. RICHARDS/AFP/Getty Images)
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PHILADELPHIA (AP) -- Commuters face a messy morning of travel a day after a winter storm brought snow and ice to many states, leaving at least 21 dead, including a pregnant woman struck by a mini-plow in New York City whose baby was then born by cesarean section in critical condition.
The next go-round of bad weather began early Friday in some places - just in time to delay tens of thousands of deliveries of Valentine's Day flowers.
The sloppy mix of snow and face-stinging sleet grounded more than 6,500 flights nationwide on Thursday and closed schools, businesses and government centers. About 1.2 million utility customers lost power as the storm moved from the South through the Northeast, dropping to about 550,000 outages, mostly in South Carolina and Georgia.
"Every time it snows, it's like, "Oh, not again,'" said Randal DeIvernois of New Cumberland, Pa., which had about 10 inches of snow by midafternoon Thursday. "I didn't get this much snow when I lived in Colorado."
The treacherous weather was blamed for nearly two dozen deaths, many of them in motor vehicle accidents.
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. She was rushed by paramedics to a nearby medical center, where her nearly full term, 6-pound, 6-ounce baby was delivered via cesarean section, hospital spokeswoman Eileen Tynion said.
The baby was in critical condition in the neonatal intensive care unit, she said.
No immediate charges were brought against the snowplow operator.
The snow, sleet and ice that bombarded the Southeast on Wednesday brought its ferocity into the Northeast a day later.
Washington, D.C., residents received 9 inches of snow Thursday, Westminster, Md., reported 19 inches, and Newark, Del., had 14 inches.
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 more than 11.
At Connecticut's Bradley International Airport, 7.4 inches of snow was recorded and there was 3.2 inches at Logan International Airport in Boston.
Across the South, the storm left in its wake a world of 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 to a hotel, where it was expected to be cozier but a lot less exciting than the night before.
"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.
Some roads around Raleigh remained clogged with abandoned vehicles Thursday morning. City crews were working to tow them to safe areas where their owners could recover them.
Around the country, this is shaping up as one of the snowiest winters on record. As of early this month, Washington, Detroit, Boston, Chicago, New York and St. Louis had gotten roughly two or three times as much snow as they normally receive at this point in the season.
The procession of storms and cold blasts - blamed in part on a kink in the jet stream, the high-altitude air currents that dictate weather - has cut into retail sales across the U.S., the Commerce Department reported Thursday. Sales dipped 0.4 percent in January.
This latest round of bad weather threatens to disrupt Friday's deliveries of flowers for Valentine's Day.
"It's a godawful thing," said Mike Flood, owner of Falls Church Florist in Virginia. "We're going to lose money. There's no doubt about it."
Ronald Reagan Washington National Airport was virtually silent Thursday, with all flights canceled. Travelers tried to catch some sleep in the terminals.
Rob Wolcott, of Washington, and his wife were trying to reach the Caribbean island of St. Kitts, where he was planning to officiate at a friend's wedding on Saturday.
The future bride and groom are "a little stressed," Wolcott said. "But they'll figure something out. They will still get married, whether or not I am the one to do the actual officiating."
Associated Press writers Kevin Begos in Pittsburgh; Michael Rubinkam in Berks County, Pa.; Kathy Matheson in Philadelphia; Sarah Brumfield and Brett Zongker in Washington; Matthew Barakat in Falls Church, Va.; and David Dishneau in Frederick, Md.; contributed to this report.