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.
More than 700,000 people, 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, closing much of Washington and threatening to drop up to 18 inches (45 cm) of snow in some areas.
The repeated 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 a glaring 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 6,349 U.S flights were canceled and another 2,396 were delayed, said flight-tracking website FlightAware.com.
About 1,000 people spent the night on cots and mats at the Charlotte Douglas International Airport in North Carolina, the airport said. 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 City schools open drew criticism from teachers and some parents, who said it was unwise to expect children to travel in dangerous conditions.
"Having students, parents and staff traveling in these conditions was unwarranted," said United Federation of Teachers president Michael Mulgrew. "It was a mistake to open schools."
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.
Francine Fencel, of Camp Hill, Pennsylvania, sent her four kids to build igloos in the yard on their sixth snow day this year, but realized the family would be losing holiday time.
"We had all these long weekends scheduled in March when the kids were supposed to be off school, but those have all been taken back because of snow days," Fencel said.
As snow days backed up, school districts from Philadelphia to Charlotte, North Carolina, were considering adding days to make up for lost classes so 180-day minimums could be met.
Parents in Charlotte complained about plans to hold classes during the first two days of spring break in April.
"We understand that families and teachers and staff have made plans," said Charlotte schools spokeswoman Tahira Stalberte. "We're looking into additional options."
Flights were delayed and canceled throughout the region, with Charlotte/Douglas International Airport, Atlanta's Hartsfield-Jackson International Airport and Philadelphia International Airport the hardest hit, FlightAware said.
Pam Foster, 38, of Auburn, Maine, was waiting at a Philadelphia Amtrak station for a train to Portland after two of her flights were canceled.
"How bad do I want to get home? I'm willing to sit on a train for ten hours," said Foster said, adding she wanted to get home to see her son, who will head to Canada to see his grandparents for next week's winter break.
There were extensive bus service cancellations in Washington, D.C., New Jersey and Philadelphia. 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.
As the snow moved north, heavy, wet flakes clung to trees and power lines in Cambridge, Massachusetts.
"It's a wet snow," said Tom Grainger, a 52-year-old police officer, as he shoveled a sidewalk. "It's hurting my back, that's for sure."