The southern USA is not known as a region of cold winters. That reputation is reserved for places like Chicago, Toronto, Montreal, Minneapolis, etc. This is a region known for relatively mild winters.
Many southern cities such as Atlanta, Charlotte, and Birmingham seem to struggle with dealing with snow. The typical theme. One inch of snow and the schools close, people raid the stores for bread and milk, roads turn into accidents waiting to happen.
Lack of experience driving in the snow can be a factor. While it can snow, cities like Atlanta and Charlotte have temperate, subtropical climates. Winters are mild compared to most of the USA. Snow is a rare. It is obvious that one who isn’t used to driving in snow will struggle with it. However, there is another factor.
Southern cities in the USA are more likely to get a ice and the snow that southern cities get is often a slushy consistency. It’s cold enough to snow, but just enough. Wet snow is the result. While it can accumulate on grass and fields, it is harder for snow to stick on warmer roads. A drop in temperature will mean ice, therefore, a dangerous road surface.
Video below explains this:
TheGeoScholar 