What is Scud (Scattered Cumulus Under Deck)?
Scud clouds are low, detached cloud fragments that form beneath storm systems, particularly under cumulonimbus clouds. They appear wispy, ragged, and fast-moving, often driven by strong winds within a storm. While scud clouds can look ominous, they do not rotate and are not a sign of tornado formation.
These clouds form when humid air is lifted rapidly in a storm’s outflow, cooling and condensing into cloud fragments. Because they often appear beneath thunderstorm clouds, they are sometimes mistaken for funnel clouds or tornadoes. However, unlike tornadoes, scud clouds do not exhibit organized rotation.
Scud clouds can indicate severe weather, especially when seen in conjunction with a thunderstorm or shelf cloud. While not inherently dangerous, they can be a visual cue that strong winds, heavy rain, or hail may soon follow.
Understanding the difference between scud clouds and true tornado formations is crucial for storm safety. If unsure, it’s always best to take shelter and monitor weather updates to confirm whether the storm poses a tornado threat.