funnel cloud

A funnel cloud is a funnel-shaped cloud of condensed water droplets, associated with a rotating column of air and extending from the base of a cloud (usually a cumulonimbus or towering cumulus cloud) but not reaching the ground or a water surface. A funnel cloud is usually visible as a cone-shaped or needle like protuberance from the main cloud base. Funnel clouds frequently form in association with supercell thunderstorms.
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A condensation funnel extending from the base of a towering cumulus or Cb, associated with a rotating column of air that is not in contract with the ground (and hence different from a tornado). A condensation funnel is a tornado, not a funnel cloud, if either a) it is in contact with the ground or b) a debris cloud or dust whirl is visible beneath it.