While it is not something we get all the time, thundersnow is actually a very common occurance in the south. Basically thundersnow is just a thunderstorm when it is cold enough to be snowing outside.

To get thundersnow, you need lightning. The lightning is generated much as it is in a spring thunderstorm, by friction of particles in the clouds. As the snowflakes collide with eachother a charge builds up and then boom, you get lightning. Typically this happens late in the winter when storms dig far to the south and have a lot of instability and turbulance. These storms tap into warm moist air and when the cold air gets wrapped into the storm from the north, thundersnow can develop.

Usually you will always get big snow totals with thundersnow as we did last night. The highest snow totals were west of Charlotte with many areas picking up 8-10 inches. We had about 4 here in town.