Where is tornado alley?
There are several areas that can be considered “Tornado Alley”. The area from central Texas to Colorado, North Dakota and Minnesota commonly gets this poorly defined label. But there is also a tornado-prone area that extends eastward from Texas to Georgia that can be considered as a Tornado Alley, and still another “alley” from Arkansas to the Ohio River and the Great Lake states of Ohio, Indiana, Illinois and Michigan. • Are there places that are not in Tornado Alley that still get more than the average number of tornadoes? Florida gets more small tornadoes per square mile than any other state, but so few big ones that most people don’t consider it as a “tornado alley”. Southern New England seems to have its own little “tornado alley” in western Massachusetts and Connecticut. • Do they really get tornadoes in California? California is a very large piece of real estate, with all kinds of curves on the coast, mountains and a huge central valley. With such a varied terrain, storms and ai
The central part of the United States is known as “Tornado Alley” because each year more tornadoes occur in this area than in any other area of the United States. Tornado Alley covers all of Oklahoma, Kansas, and Nebraska, and part of Texas, Arkansas, Missouri, Iowa, South Dakota, Colorado and Wyoming. The Central Plains provide three requirements necessary for tornado formation: • Violent thunderstorms that are formed by cool dry air from the north and the warm, humid Gulf of Mexico air • Low level shifting winds • Very little competition from nearby storms It is the unique combination of atmospheric “parameters” — a large moisture supply, low-level wind shear, a drying and cooling middle atmosphere, and features, such as the dryline and a convective cap — that turn the plains into a tornado alley.
The Wizard of Oz movie in 1939 helped Kansas and the Great Plains become known as part of “Tornado Alley” – the region of the United States often visited in late spring and early summer by dangerous, sometimes violent, tornadoes. Part of the reason why is that the “dryline” — a front separating moist Gulf of Mexico air from dry air from the Southwest — often sits across these states, helping spawn tornado-producing thunderstorms. The Glossary of Meteorology published by the American Meteorological Society defines “Tornado Alley” as “a term often used by the media to denote a zone in the Great Plains region of the central United States, often a north-south-oriented region centered on north Texas, Oklahoma, Kansas, and Nebraska, where tornadoes are most frequent.” It turns out that the last phrase isn’t correct. If we looked for the state that gets the most tornadoes per square mile of countryside, the “honor” belongs to Florida. Other states also have as many or more tornadoes per squ
