Tornado Alley

Tornado Alley (English, Tornado Alley ) is a colloquial term, with which a particular area is referred to in the Midwestern United States, where there is a particularly high probability of tornadoes.

Geography

Although there are tornadoes in all parts of the United States, their frequency in the Great Plains area between the Rocky Mountains and the Appalachian Mountains and in Florida is the highest. So-called Twister occur in Texas most common. The area affected by tornadoes in Florida is at its greatest, however the local tornadoes are rather weak and usually short-lived. The lowest probability of tornadoes in the U.S., there are in the far west and northwest.

Definition

An official definition, such as the National Weather Service, the National Weather Service of the United States for the term does not exist. The Content with which the term is being filled, differs to some extent, depending on what criteria are applied.

According to the most widely used definition belong to the tornado Alley those areas where the strongest tornadoes occur. Thus, the northern part of Texas, as well as almost all states of north thereto, ie Oklahoma, Kansas, Missouri, Nebraska and South Dakota.

Frequency

Another definition does not ask for the strength of individual tornadoes, but according to the frequency in relation to other, less violent affected regions. Under this method, the Tornado Alley covers an even much larger sphere of influence. In addition to the above-mentioned areas then includes the entire lowlands along the Mississippi River and the Ohio River and to the lower valley of the Missouri and the entire southeastern United States to Florida.

Season

The season is also important. The greatest frequency of tornadoes, the " tornado season " varies from region to region. In winter, especially the states are strongly affected in the southeastern United States. From March to May, the focus moved to the Midwest. Once the temperature in the summer months reaches its peak, the biggest threat lies further to the north, that is, in the northern Prairiestaaten. Regardless, include the Central Plains basically all year sphere of influence to the tornado Alley, since there is always strong temperature fluctuations are part of the weather patterns.

Regional variations

In the southern United States, particularly in the lower valley of the Mississippi River and in the upper reaches of the river Tennessee also referred to as the Dixie Alley - an area that may occur in the particularly strong tornadoes. In this region, the number of tornadoes by people lost their lives is higher than in the actual Tornado Alley, but this is due to the higher population density.

Effects

At the heart of Tornado Alley certain building regulations are more stringent than in other parts of the United States, particularly as regards the construction of roofs and the compound of houses with their foundations. Other usual precautionary measures include the construction of shelters and the installation of tornado sirens. Even the weather reports in the mass media provide to the reporting of and protection from tornadoes one.