An army of emergency crews were gearing up for battle Wednesday with a vicious--and rare--ice storm in Georgia that had already cut off power for thousands of customers and left the streets of Atlanta looking like a sci-fi wasteland.
More than 70,000 customers in Louisiana, Arkansas, Texas, Mississippi, Alabama and the Carolinas were without power early Wednesday. But Georgia was bearing the brunt of the wicked weather, with more than 80,000 customers in the dark Wednesday, while emergency planners urged drivers across the state to stay off "deceptively dangerous" roads.
Metro Atlanta was a veritable ghost town as an eerie calm settled over desolate streets slick with ice. The highways were deserted as freezing rain kept drivers at home. At local retailers, shoppers scrambled to stock up on supplies before the brunt of the storm came crashing down.
As many as 5,000 state personnel plus an additional 3,000 support crews were fanned out across the region and at the ready, according to Brian Green with utility company Georgia Power. The National Weather Service issued an ominous warning for a potentially "catastrophic event," urging Georgians to "be prepared to be without power in some locations for days and perhaps as long as a week."
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As of mid-morning Wednesday, 3,003 flights across the U.S. were canceled and 3,198 delayed — over 2,000 of them at the Atlanta Hartsfield-Jackson hub, where only 259 flights were scheduled to fly today, an airport spokesman said.
"Be prepared for power outages, long periods in the cold/dark," The Weather Channel tweeted as the the first freezing rain fell in what was forecast to be a 36-hour deep freeze.
As it crawls eastwards, the same weather system was forecast to dump up to 12 inches of snow on New York City, Philadelphia and Washington, D.C., on Thursday, snarling travel plans for millions.
"There will be disruption," Weather Channel lead meteorologist Kevin Roth said. "The whole region will be in a deep freeze."
Desperate to avoid a repeat of January's fiasco, when children were stranded in school gyms overnight and drivers camped in their cars on frozen interstates for 24 hours, authorities in Atlanta had issued dire warnings.
"This would have been bad timing for the morning commute, but with so many people heeding the warnings to stay home, there should be less disruption," Roth said.
"A lot of people might work from home – that is, if their power stays on," he added.
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Georgia's state operations center issued an advisory early Wednesday warning of "extremely hazardous conditions" that will cause power outages "and substantial structural damage due to falling trees and ice."
"All motorists are urged to stay off of the roads as the threat of icy conditions continues to increase throughout the day," the advisory said.
"We're not kidding. We're not just crying wolf," Georgia Governor Nathan Deal said Tuesday. "It is serious business."
Georgia Power spokesman Brian Green said between 4,000 and 5,000 power crews and support personnel were standing by to react to power outages, with an additional 3,000 workers on standby in surrounding states.
President Barack Obama declared an emergency in Georgia, calling on federal agencies to lend a hand to state and local response efforts. And the Federal Emergency Management Agency announced that federal emergency aid has been made available to Georgia.
Amtrak said it would suspend service Wednesday on 10 trains in Georgia, Florida and the Carolinas "to reduce the exposure of Amtrak passengers, crews and rail equipment to extreme weather conditions."
With as much as a half-inch of solid ice expected to coat roads and power lines, the governors of both Carolinas, Alabama, Virginia, West Virginia and Maryland also declared states of emergency for much or all of their states. South Carolina Gov ernor Nikki Haley flatly said, "No one should be on the roads tomorrow at all."
"We do need to brace ourselves," she said. "This is going to be a pretty bad ice storm."
However, the focus was expected to shift northward later Wednesday, as the same weather system turns into a classic Northeaster - dumping snow on the Mid-Atlantic and New York, but the risk of power outages was likely to be lower.
"There shouldn't be as much ice further north," Roth said.
At least six deaths were already blamed on the storm Tuesday as it gathered power over Texas and Mississippi.
Four people were killed in separate accidents on icy north Texas roads, including a Dallas firefighter who was knocked off an interstate ramp, NBCDFW reported. And two were killed in separate accidents in Mississippi, the state Highway Patrol said.
—By Alastair Jamieson of NBC News. M. Alex Johnson and Daniel Arkin contributed to this report.