What violently rotating column of air touches the ground in a thunderstorm? A tornado is the answer. It is a rotating air vortex connected to the ground and usually associated with the base of a cumulonimbus cloud.
Many tornadoes develop from severe thunderstorms called supercells, whose rotating updrafts can become concentrated into a narrow vortex. Falling pressure and condensation may create a visible funnel cloud, but the funnel itself is not the tornado’s entire structure. A tornado can exist even when the condensation funnel is difficult to see; dust, debris, or surface damage may reveal its contact with the ground.
Tornadoes vary enormously in size, duration, and strength. Most are relatively short-lived, but the most powerful can become kilometres wide and travel long distances. A waterspout is a tornado over water, while a dust devil is generally a smaller, fair-weather vortex that is not produced by a thunderstorm. Hurricanes are much larger rotating storm systems, not columns of air touching the ground.