Winter Storm Iago will spread both snow and rain across the South and into the Mid-Atlantic Thursday into Thursday night and early Friday.
The primary mechanism for this storm is a potent area of low-pressure aloft that will move through the Deep South Thursday and head into the Atlantic Ocean by early Friday.
Ahead of this system, heavy rain and flooding will be a concern in parts of the Appalachians and Southeast.
As for the wintry side, we will see rain changing to snow from parts of Mississippi, northern Alabama, northern Georgia and eastern Tennessee to the Southern Appalachians, northern North Carolina and Virginia Thursday morning through Thursday evening.
(MAP: Winter storm alerts)
We expect the heaviest accumulations, 6 inches or more, to be in the higher elevations of the Southern Appalachians.
Parts of Mississippi, northern Alabama and far northern Georgia could see anywhere from a dusting to a few inches. Wet pavement could freeze into patches of ice (black ice) on roadways Thursday night into Friday morning.
To the east of the Appalachians, a wide area of 1 to 3 inches of accumulation is possible from North Carolina to much of the southern half of Virginia and the southern Delmarva Peninsula. Embedded in this swath will be higher totals of 3 to 6 inches. We expect the 1"+ accumulating snow to remain south of Washington, D.C.
In many of these areas outside mountain locations, this will be the first measurable snow of the season.
Though snowfall with this system will be of short duration, it could also be heavy at times. At first, due to mild temperatures recently, initial snow accumulations in the lower elevations outside the Appalachians will be on grassy and elevated surfaces. However, it won't take long for heavier snowfall rates to accumulate on road surfaces as well.
As the storm shifts out to sea early Friday, it may move close enough to the Northeast coast to bring some snow to parts of the southern New Jersey coast, eastern Long Island and far southeastern New England.
(MAP: Northeast snow forecast)
Leave extra time for your Friday morning commute in these areas, due to this freshly fallen snow.
Only a few tire tracks can be seen in the windswept snowfall early Thursday morning, Jan. 17, 2013 on Lakeland Drive, usually a busy street.