A tornado is a narrow column of air that spins rapidly around an extremely localised but intense low-pressure centre in contact with the ground. It is commonly marked by a funnel cloud but may be observed as debris is thrown up from the surface.
A tornado is a narrow, rapidly spinning column of air around an intense low pressure centre that reaches the ground from cumulonimbus clouds (also known as thunderstorm clouds). Tornados have a narrow width, usually up to 100m but the damage can be concentrated and severe.
As they develop, funnel shaped clouds extend from the base of the cloud and when these reach the ground, a tornado is formed. Tornadoes which occur over water are referred to as a waterspout and those which do not touch ground are referred to as a funnel cloud. The highest surface wind speed ever recorded of 302mph is a result of the 1999 Oklahoma tornado outbreak.
Last updated: 26 July 2013