COLORADO SPRINGS, Colo. — Scud clouds are often confused for tornadoes and funnels, but they are very different. They are harmless clouds that can spark a lot of concern when they form if you don’t know how to tell the difference.
Scud clouds form in association with thunderstorms. All thunderstorms have a downdraft that expels air from the storm down to the ground. If there is enough moisture beneath the storm, these downdrafts can form a detached cloud beneath the storm that reaches toward the ground. This is called a scud cloud.
Because they form with thunderstorms and can have a similar shape to funnels, they are often confused for them.
There are a few key things to look for so you can tell what you are seeing.
- Does the cloud have smooth edges or wispy edges?
- Does it have an irregular form or is it shaped like a cone or snaking rope?
- Is there rotation present in the storm?
If the cloud has jagged/wispy edges it is probably a scud cloud. Tornadoes and funnels typically have smoother sides.
If it has an irregular form, that is another key sign that it is not a tornado.
The rotation is the final clue to let you know what you are seeing. Scud clouds CAN form when rotation is present, so this does not rule it out as a scud cloud even if the storm is rotating. Instead, look for the lack of rotation. If the storm has no rotation it is probably not a tornado. Tornadoes must have this to form.
If you’re not sure what you are looking at, take a picture and send it to FOX21 or to the National Weather Service. We can help you figure it out.