Definition: In terms of tornadoes, one of the most dangerous parts of a funnel cloud can be the debris cloud. The wind speeds of a tornado can pick up very heavy objects and swirl them around in a dense cloud around the base or the funnel cloud itself. In fact, items such as trucks, tractors, cars, animals, and people can be swirled around in a debris cloud.
Not all tornadoes produce heavy debris clouds and not all tornadoes have enough sustained winds to pull up large objects. Therefore, the primary component of most debris clouds is dust and small bits of debris.