Emergency management workers in the Atlanta area were preparing to spring into action as rain — and temperatures — were falling early Wednesday, potentially leading to “catastrophic” ice conditions across the region.

Already, Georgia Power was reporting thousands of power outages around the state. And forecasters and officials said the number of outages would probably grow throughout the day. In north Georgia, morning snow was falling. Other areas of the South, from Louisiana to South Carolina, and the mid-Atlantic also are expected to get socked with a wintry mix of ice, snow and freezing rain.

Atlanta and the surrounding region dodged the first punch of a dangerous winter storm Tuesday, but forecasters warned that the second punch would likely bring a thick layer of ice and heavy winds that could knock out power to thousands and leave people stranded in their cold, dark homes for days. National Weather Service forecasters used unusual dire language in warnings and memos early Wednesday, and they said that while a foot of snow could fall in some parts of Georgia, “it is the ice that will have the catastrophic impacts.”

Elected leaders and emergency management officials began warning people to stay off the roads, especially after two inches of snowfall caused an icy gridlock two weeks ago and left thousands stranded in vehicles overnight. It seemed many in the region around the state's capital obliged as streets and highways were uncharacteristically unclogged Tuesday.

Eli Jacks, a meteorologist with National Weather Service, said forecasters use words such as “catastrophic” sparingly.

“Sometimes we want to tell them, 'Hey, listen, this warning is different. This is really extremely dangerous, and it doesn't happen very often,'” Jacks said.

The service's memo early Wednesday called the storm “an event of historical proportions.”

It continues: “Catastrophic ... crippling ... paralyzing ... choose your adjective.”

Jack said three-quarters of an inch of ice would be catastrophic anywhere. But the Atlanta area and other parts of the South are particularly vulnerable: Many trees and limbs hang over power lines. When ice builds up on them, limbs snap and fall, knocking out power.

Hundreds of Georgia National Guard troops were on standby in case evacuations were needed at hospitals or nursing homes, and more than 70 shelters were set to open. President Barack Obama declared a state of emergency in Georgia, ordering federal agencies to help the state and local response during the storm. Deal said a priority for that request was generators.

Around the Deep South, slick roads were causing problems. In North Texas, at least four people died in traffic accidents on icy roads, including a Dallas firefighter who was knocked from an Interstate 20 ramp and fell 50 feet, according to a police report.

Also in Texas, an accident involving about 20 vehicles was reported Tuesday along an icy highway overpass in Round Rock, just north of Austin. Police dispatchers said no serious injuries were reported and the roadway was cleared by Tuesday evening.

In northeastern Alabama, two National Guard wreckers were dispatched to help clear jackknifed 18-wheelers on Interstate 65. Alabama Gov. Robert Bentley said one lesson learned from the storm two weeks ago was to get those wreckers organized earlier.

Parts of northeast Mississippi could see up to 4 inches of snow. South Carolina, which hasn't seen a major ice storm in nearly a decade, could get a quarter to three-quarters of an inch of ice and as much as 8 inches of snow in some areas.