It's early December...surface temps (when not yet saturated) are not always the best indicator of the depth of a cold air mass or of the flow at the mid and upper levels which have more to say at determining storm track and snowfall. That said your concern for places south of is on the coastal plain is legit. It's close to mixing if things break 1-2 degrees warmer. But I think dewpoints suggest if they will be ok. Inland on the piedmont and the mountains make no mistake this will be historic for them. Keep in mind a 10"+ storm is historic for places south of DC outside high elevations. A 10" storm in Richmond would immediately jump into 16th place all time. 13" would get into the top 10! A pretty large area of northwest NC and southwestern VA west of the fall line is going to get 10-15" with some localized places pushing 20. That's a rare significant event for that area. I wouldn't dismiss it so readily.