Monthly Archives: December 2012

Size and shape

Most tornadoes take on the appearance of a narrow funnel, a few hundred yards (meters) across, with a small cloud of debris near the ground. Tornadoes may be obscured completely by rain or dust. These tornadoes are especially dangerous, as even experienced meteorologists might not see them.[22] Tornadoes can appear in many shapes and sizes. Small, relatively … Continue reading

Outbreaks and families

Occasionally, a single storm will produce more than one tornado, either simultaneously or in succession. Multiple tornadoes produced by the same storm cell are referred to as a “tornado family”.[19] Several tornadoes are sometimes spawned from the same large-scale storm system. If there is no break in activity, this is considered a tornado outbreak (although the term “tornado … Continue reading

Funnel Cloud

A tornado is not necessarily visible; however, the intense low pressure caused by the high wind speeds (as described by Bernoulli’s principle) and rapid rotation (due to cyclostrophic balance) usually causes water vapor in the air to condense into cloud droplets due to adiabatic cooling. This results in the formation of a visible funnel cloud or condensation funnel.[17] There is … Continue reading

Definition

A tornado is “a violently rotating column of air, in contact with the ground, either pendant from a cumuliform cloud or underneath a cumuliform cloud, and often (but not always) visible as a funnel cloud”.[14] For a vortex to be classified as a tornado, it must be in contact with both the ground and the cloud base. Scientists … Continue reading

Meaning

The word tornado is an altered form of the Spanish word tronada, which means “thunderstorm”. This in turn was taken from the Latin tonare, meaning “to thunder”. It most likely reached its present form through a combination of the Spanish tronada and tornar (“to turn”); however, this may be a folk etymology.[10][11] A tornado is also commonly referred to as a “twister”, and is also … Continue reading

Tornados

A tornado is a violently rotating column of air that is in contact with both the surface of the earth and a cumulonimbus cloud or, in rare cases, the base of a cumulus cloud. They are often referred to as twisters or cyclones,[1] although the word cyclone is used in meteorology, in a wider sense, to name any closed low pressure circulation. Tornadoes come in many shapes and sizes, but … Continue reading