KNOXVILLE, Tenn. (WVLT) -- A viewer sent us a video, fearing a tornado was developing in the storm clouds moving in. It’s a common mistake with the particular cloud type that she was actually witnessing.
Deb spotted scud clouds. Scuds are ragged, low clouds. You might spot them floating below storm clouds.
The question we often get is, is it a tornado? By definition a tornado is a violently rotating column of air in contact with the ground. A funnel clouds is what it is called if it’s not touching the ground.
There are some other types of clouds associated with thunderstorms.
Wall clouds are thick clouds that drop down out of the base of the higher clouds. These can spawn tornadoes, but the wall cloud itself isn’t the funnel or tornado.
Tail clouds can form off a wall cloud, and are also commonly confused for the makings of a tornado. In fact, these clouds are as low as the wall cloud and fan out like a tail.
Shelf clouds can be ominous and look more like a dramatic change in weather, as the storm approaches. They’re a low, horizontal wedge-shaped cloud, associated with a thunderstorm gust front.
The National Weather Service offers free spotter training courses, where they go over this important information in even more detail. If you have any questions regarding classes through the Morristown office, please call Anthony Cavallucci at (423) 586-3771 or email at Anthony.Cavallucci@noaa.gov.