tornado

A tornado, also known as a twister, is a rapidly rotating column of air that extends vertically from the surface of the Earth to the base of a cumulonimbus or cumulus cloud. Tornadoes are often (but not always) visible in the form of a condensation funnel originating from the cloud base, with a cloud of rotating debris and dust close to the ground. Most tornadoes have wind speeds less than , are about across, and travel several kilometers (a few miles) before dissipating. The most extreme tornadoes can attain wind speeds of more than , can be more than in diameter, and can stay on the ground for more than .

Types of tornadoes include the multiple-vortex tornado, landspout, and waterspout. Waterspouts are characterized by a spiraling funnel-shaped wind current, connecting to a large cumulus or cumulonimbus cloud. They are generally classified as non-supercellular tornadoes that develop over bodies of water, but there is disagreement about whether to classify them as true tornadoes. These spiraling columns of air often develop in tropical areas close to the equator and are less common at high latitudes. Similar phenomena in nature include the gustnado, dust devil, fire whirl, and steam devil.