By Victoria Cavaliere and Chris Francescani
NEW YORK, Feb 13 (Reuters) - A winter storm that froze the U.S. southeast in its tracks pushed north on Thursday, with driving winds and heavy snow snarling travel and closing many schools from Washington to Connecticut, creating havoc for winter-weary parents.
About 740,000 businesses and homes, including residents of Georgia and South Carolina hit by a heavy blast of ice a day earlier, were without power as the storm made its way up the coast and threatened to drop up to 18 inches (45 cm) of snow in some areas.
With renewed snowfall shrouding the U.S. Capitol after nightfall, the National Weather Service said heavy snow would continue for the northeast but would begin to taper off from south to north on Friday morning.
Coastal New England is forecast to see rain, with sleet or freezing rain mixed in, it said.
Repeated winter storms are taking a toll on schools and families, as snow-related cancellations left parents scrambling to find child-care options and administrators looking at making up lost days by extending classes into the summer.
New York City Public Schools, having taken only one snow day this year, proved an exception and remained open.
Jane Mills, a former teacher from Nashville, Tennessee, who was walking with her 6-year-old granddaughter in Brooklyn, said it was "absolutely ridiculous" that public schools were open.
"It's a danger to the students traveling in buses or cars. It's a danger to teachers commuting," said Mills.
About 6,900 U.S flights were canceled and another 3,900 were delayed, said flight-tracking website FlightAware.com.
Charlotte/Douglas International Airport, Atlanta's Hartsfield-Jackson International Airport and Philadelphia International Airport were the hardest hit, FlightAware said.
About 1,000 people spent the night on cots and mats at the Charlotte airport. Across the state in Durham, motorists stuck in traffic that resembled the gridlock mess in Atlanta two weeks ago found refuge for the night at a mall.
The storm system, which has dumped heavy snow, sleet and freezing rain from eastern Texas to the Carolinas since Tuesday, was blamed for at least 15 deaths in the South.
In New York, a pregnant 36-year-old woman was killed by a private snow plow in a parking lot in Brooklyn, said police spokeswoman Sergeant Jessica McRorie. Doctors at a nearby hospital were trying to save the baby.
DECISIONS ON SCHOOLS
The decision to keep New York schools open drew criticism from teachers and some parents, who said it was unwise to expect children to travel in dangerous conditions.
"It was a mistake to open schools," said United Federation of Teachers President Michael Mulgrew
New York City Mayor Bill de Blasio defended the decision, saying the city was not facing the kind of overwhelming snow that would make it impossible for kids to get to school.
Many other districts around the region kept students home. As snow days stacked up, school districts from Philadelphia to Charlotte, North Carolina, were considering adding days to make up for lost classes so 180-day minimum requirements could be met.
Philadelphia Mayor Michael Nutter urged teenagers stuck at home to use the snowstorm to build a college fund.
"Grab a shovel," Nutter said. "There is much money to be made."
The weather also slowed business for flower shops banking on big day of deliveries on Friday for Valentine's Day.
Oscar Acosta, a florist at Clinton Flower Shop in New York, was busy readying bouquets and dealing with customers but conceded that business had been slowed because of the storm.
"I don't see a very good day tomorrow. Not this year," he said.
There were extensive bus service cancellations in Washington, New Jersey and Philadelphia and Connecticut joined a raft of other states in declaring a state of emergency.
New Jersey Transit, the third-biggest U.S. commuter system, began to restore normal service on Thursday afternoon. In Jersey City, New Jersey, the roof of a Verizon Communications Inc maintenance garage collapsed under more than a foot (30 cm) of wet snow, but no one was hurt, a company spokesman said.
Federal offices in Washington, and state offices in Connecticut and western Massachusetts were closed. Rhode Island's state legislature called off its sessions for the day.
Winter storm warnings were in effect from North Carolina to Maine. Some 742,603 homes and businesses were without power from Florida to New Jersey, with Georgia and South Carolina, served by utilities including Georgia Power and Duke Energy Corp hardest hit, the Energy Department said.
In Milford, Connecticut, Danny Hooks, 56, used his snowblower for the 12th time this winter to clear paths for himself and his neighbors.
"Enough is enough, we just can't catch a break. This is crazy and there's no end in sight," said Hooks, a retired sanitation foreman for the city.