(Adds cleanup efforts in Atlanta, weather forecast)
By David Beasley
ATLANTA, Jan 29 (Reuters) - A rare ice storm turned Atlanta into a slippery mess on Wednesday, stranding thousands for hours on frozen roadways and raising questions about how city leaders prepared for and handled the cold snap that slammed the U.S. South.
The storm, which has killed at least seven people, on Tuesday swept over a region of about 60 million largely unaccustomed to ice and snow - stretching from Texas through Georgia and into the Carolinas - and forecasts called for more freezing weather on Thursday.
Overnight temperatures in the Atlanta region are expected to remain well below freezing, with temperatures in the U.S. Southeast dropping into the teens Fahrenheit (minus 10 to minus 7 Celsius) on Thursday. That could hinder efforts to clear ice-covered roads and abandoned cars that litter the region.
Georgia officials said on Wednesday that the real progress in cleaning up the region would not come until after the icy roads begin to thaw, which could happen midday Thursday, meteorologists said.
Atlanta Mayor Kasim Reed came under fire for his response to a storm that trapped hundreds of children in schools overnight, some without provisions, and created traffic jams stretching for miles on roads coated with 2 inches (5 cm) of snow.
"Folks are angry with the mayor of Atlanta, with the governor," said Flavia DiCesare, 54, who spent the night in her office at Cox Enterprises in Atlanta, about 30 miles (48 km) from home.
The mayor said schools, businesses and government offices were partly to blame for sending all the workers home just as the storm was rolling in.
"During the day, we have a million to 1.2 million people in this city and all those people were out in very bad weather. It hampered our ability to get our equipment on the ground and to prepare our roads for that," Reed told a news conference.
"The error - and we have shared responsibility for the error - the error was letting everybody out at once," he said.
Georgia Governor Nathan Deal said all of Atlanta's school children had been safely returned to their families by Wednesday evening, with help from the National Guard and State Patrol.
Deal had earlier angered many - including local meteorologists - when he described the storm late Tuesday as "unexpected."
The comments prompted a sharp reaction from many residents - and meteorologists. In a blog published Wednesday, American Meteorological Society President J. Marshall Shepherd defended local weather forecasters, declaring "the Atlanta forecast was very good."
The one-day snowfall of 2.6 inches (6.6 cm) ranked as the 20th heaviest in Atlanta, which has recorded a daily snowfall of an inch or more 55 times since 1928, according to the National Weather Service.
"SCENE FROM 'WALKING DEAD'"
The city's highways became parking lots and thousands of motorists, still stuck 24 hours after the storm hit, were seeking help and food. Workers who could not get home were setting up makeshift accommodations in stores and offices.
The roads, littered with stranded cars, looked like a scene from the television show "Walking Dead," said DiCesare, who spent the night in her office with about 100 other employees.
"It looks like zombies walking on the side of these roads," she said.
Predicted or not, Wednesday's sudden cold snap stunned the city.
"We're in complete gridlock down here," said Steve Rose, a police captain in Sandy Springs, Georgia, during Tuesday evening rush hour. "It's kind of embarrassing, but we got 3 inches of snow and we're screwed."
About 800 traffic accidents were reported in the city, but there were no serious injuries, officials said. At least five deaths in Alabama and two in Georgia were blamed on the weather.
Latasha Wade, 38, said she was awaiting word of her 31-year-old brother, last heard from Tuesday night after his car was stranded in Atlanta.
"I don't know if he's laying out in the snow or what," she said. "It's the most hurtful thing because I don't know anything that's going on with my brother."
The storm took a toll on air travel across the region, with more than 2,600 U.S. flights canceled and hundreds of others delayed, according to flight tracking website FlightAware.com.
Nicole Lynch, 22, a student at Kennesaw State University, was among the Atlanta motorists who found themselves stuck in frustrating traffic snarls.
"They should have at least warned any sort of road crew, or taken some precautions. They should have canceled school a lot sooner than they did," Lynch said. "It's a lot of shudda, cudda, wuddas."
A Facebook page called "Stranded Motorists Help Jan 28, 2014" which has more than 10,000 members, amassed entries from frustrated drivers and volunteers trying to come to their aid after the daylong gridlock in the Atlanta metro area.
Rachel Richter, 30, said she finally abandoned her car, after sitting in a traffic jam for six hours.
"It was more the frustration that it was just complete gridlock. Nothing was moving at all," she said. "You moved like an inch in two hours." (Additional reporting by Karen Jacobs in Atlanta; Verna Gates in Birmingham, Alabama; Ellen Wulfhorst in New York; Kathy Finn in New Orleans; and Harriet McLeod on Charleston, South Carolina; Writing by Jon Herskovitz; Editing by Gunna Dickson and Lisa Shumaker)