Snow could blanket the South this weekend in major winter storm

 

Significant snow is expected -- but not certain -- across the mountains of northeast Georgia and North and South Carolina. Estimates range from 1 foot to almost 2 feet in the mountains and foothills west of Interstate 85. Parts of North Carolina could see record snowfall, described by the National Weather Service called a "once-in-a-generation event." That includes Winston-Salem and Asheville, which could get a foot of snow; Raleigh, with 1 to 2 inches possible; and Charlotte. Greenville, South Carolina is likely to get 1 inch of snow.

While most forecast models keep the winter precipitation tucked into Carolinas, one shows possible freezing rain reaching down the I-85 corridor on Sunday night into Monday to Atlanta, which also could get a dusting of snow Monday afternoon.

Snow totals east of I-85 will on depend on a regional weather phenomenon called "cold-air damming" or "the wedge" -- when cold air pushes in from the northeast against the Appalachians. The mountain range acts as a dam, keeping the cold air pooled like a lake. Warmer air in this scenario would reduce snow accumulation. There's another phenomenon called a "warm nose" that would allow warmer air to mix in above the "'wedge," bringing a more wintry mix Saturday evening and overnight into Sunday morning before snow moves in northwest of I-85.