Tornado: Overview

Although, in regards to the number of incidents the United States has a higher count, the United Kingdom is documented as the most susceptible country to tornados proportional to land area.

Tornados are violent, spinning wind storms, funnel shaped, with a narrow base. Tornados are extremely destructive, though relatively short incidents that are nearly always visible upon formation, but somewhat shrouded until the moment of release. While they have been recorded throughout the world, the region with the greatest number of tornados, annually, runs through the American Midwest and Southern regions. Although, in regards to the number of incidents the United States has a higher count, the United Kingdom is documented as the most susceptible country to tornados proportional to land area.

Tornados form from a special type of thunderstorm known as a super-cell thunderstorm, though they are also found within squall markings and hurricanes. Though tornados are not yet fully understood, the current models show them being formed when a burst of cool air supersedes a layer of warm air, forcing the warm air to quickly rise. So, when thunderstorms develop, this rise of air, results in an increase in wind speed, generally in addition to wind shear, creating a horizontally based, rotating area of air. The internal updrafts of the thunderstorm works like a suction, and draws up this area of rotation from a horizontal to a vertical alignment. If this rotation intensifies, a funnel cloud could develop into a situation where the water vapor of the cloud is drawn, or pushed down towards the ground. When the funnel cloud follows the intensity of the vortex towards the ground level is the stage known as " touching down," which indicates the formation of a tornado. Sometimes, however, this is indicator can be misleading, as tornados can have a partial funnel cloud, or be wholly invisible. It is not a rarity to find tornados suddenly becoming visible, as they move through the air, accruing debris from the land it crosses through.

Tornados are slightly different in respect to their physiological locations. Tornados in the northern hemisphere rotate in a counter clockwise, cyclonic direction as warmer air thunderstorms form in sweeping belts from the north, while the jet streams originate from the west, while tornados in the southern hemisphere rotate in a clockwise direction. Oddities are known to occur though, with 1 in about every 150 tornados in the northern hemisphere being a clockwise rotating storm. Like their differing spin patterns, no two tornados are ever the same- this holds true for degree of intensity and behavior. And while some tornados have been known to strike the same geographic path, the likelihood of precisely forecasting the place and time of a tornado strike is negligible.

Tornados are classified in terms of intensity through the Fujita-Pearson Tornado Scale. Intensity is defined through either data from a high resolution doppler radar or empirical structural damage. The Fujita scale ranges from F0 to F5, with F0 showing minimal damage and F5 showing incredible devastation.

 

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