Tornado Alley in the U.S.

Tornado Alley

There are two areas in the country where tornadoes occur most often. One is Florida and the other, known as "Tornado Alley", is in the south-central part of the U.S. The climate of Florida is distinguished by frequent, almost daily thunderstorms. Plus, each year the Florida peninsula is affected by tropical storms and hurricanes. Moving towards the shore they clash with the embedded convective storms in the rain bands and create tornadoes. Even though the tropical storms or hurricanes are very severe, the tornadoes they produce (sometimes in the form of water spouts) are typically weaker and less devastating than tornadoes caused by non-tropical thunderstorms.

"Tornado Alley" is a region in the southern part of the central United States that is regularly affected by tornadoes. Each year tornadoes in this area occur mostly in late spring, or in the early fall. The Gulf Coast area is nicknamed "Dixie Alley" as many tornadoes tend to develop there in the period from late fall to December.

There are no fixed boundaries of Tornado Alley, but typically it encompasses area stretching from central Texas, north to Iowa, and from central Kansas and Nebraska east to western Ohio. From the meteorological point of view, the location of the area nicknamed as Tornado Alley is favorable for the supercell thunderstorms that may produce violent (EF-2 or stronger) tornadoes.

In general, about 80% of tornadoes in the United States are rather weak (EF-0 or EF-1) and approximately 95% of all tornadoes in the U.S. fail to reach EF-3 intensity. The rest tornadoes are classified as violent (EF-3 and greater), with only 0.1% of them reaching EF-5 status (which means winds speed of more than 200 mph and total ruination). According to statistics, at least 1,000 tornadoes hit the United States each year. This means that 20 of them may be very strong and possibly one might be extremely violent (EF-5).