ATLANTA, Jan 21, (AP): With many Americans still recovering from multiple blasts of snow and unrelenting freezing temperatures in the nation’s northern tier, a new storm is set to emerge this weekend that could coat roads, trees and power lines with devastating ice across a wide expanse of the South. The storm arriving late this week and into the weekend is shaping up to be a "widespread potentially catastrophic event from Texas to the Carolinas,” said Ryan Maue, a former chief scientist at the National Oceanic and Atmospheric Administration.

"I don’t know how people are going to deal with it,” he said. Forecasters on Tuesday warned that the ice could weigh down trees and power lines, triggering widespread outages. "If you get a half of an inch of ice - or heaven forbid an inch of ice - that could be catastrophic,” said Keith Avery, CEO of the Newberry Electric Cooperative in South Carolina.

Here's what to know: The National Weather Service warned of "great swaths of heavy snow, sleet, and treacherous freezing rain” starting Friday in much of the nation’s midsection and then shifting toward the East Coast through Sunday. Temperatures will be slow to warm in many areas, meaning ice that forms on roads and sidewalks might stick around, forecasters say.

The exact timing of the approaching storm - and where it is headed - remained uncertain on Tuesday. Forecasters say it can be challenging to predict precisely which areas could see rain and which ones could be punished with ice. An extremely cold arctic air mass is set to dive south from Canada, setting up a clash with the cold temperatures and rain that will be streaming eastward across the southern US.

"This is extreme, even for this being the peak of winter,” National Weather Service meteorologist Bryan Jackson said of the cold temperatures. When the cold air meets the rain, the likely result will be "a major winter storm with very impactful weather, with all the moisture coming up from the Gulf and encountering all this particularly cold air that’s spilling in,” Jackson said. An atmospheric river of moisture could be in place by the weekend, pulling precipitation across Texas and other states along the Gulf Coast and continuing across Georgia and the Carolinas, forecasters said.