Tornadoes happen when warm, moist air masses and cold, dry air masses collide to cause large thunderstorms. Not all thunderstorms produce tornadoes, and scientists are not certain which factors are directly responsible for their formation. They do know that in many cases, horizontal spinning movements in the air can be lifted vertically. Once vertical, its base may span up to three miles from one side to the other.
While tornadoes are theoretically possible in any thunderstorm, they are far more common in the United States and Canada than any other country. They are especially common in a narrow slice of land called Tornado Alley. Tornado alley includes part of Kansas, Nebraska, Texas, South Dakota and Oklahoma. The reason that so many tornadoes occur in this area is that the Gulf of Mexico and Canadian tundra are found at each end. The Gulf of Mexico provides a constant source of warm, wet air, while the air flowing in from Canada is almost always cold and dry. The two air masses often collide over Tornado Alley, causing the frequent tornadoes.
Tornadoes are one of the most destructive forces in nature, and they can cause widespread damage and casualties. Tornadoes are ranked via a scale called the Enhanced Fujita Scale. Some tornadoes have had winds that exceeded 300 miles per hour.Learn More
The only significant similarity between tornadoes and hurricanes is that they both produce high-speed winds. Tornadoes form as the result of lingering strong vertical wind velocity and vertical temperature changes. Hurricanes form as the result of extended periods of weak vertical wind velocity and relatively low changes in atmospheric temperature.Full Answer >
A tornado is essentially a violently rotating column of air moving at speeds up to 300 miles per hour. It is also likely to contain objects it has come in contact with on the ground, though the objects are rarely intact.Full Answer >
The largest concentration of tornadoes occur in Tornado Alley, which encompasses most of the Great Plains of the central United States. One quarter of the most significant tornadoes in the United States occur in Tornado Alley. Oklahoma experiences the highest number of tornadoes and the most severe tornadoes in the United States.Full Answer >
Tornadoes injure and kill people, destroy property, take a heavy financial toll, disrupt communication and create severe anxiety. The number of deaths due to tornadoes varies significantly from year to year. For example, according to NOAA, in 2008, 126 people died, but in the following year, only 21 lives were lost. Tornadoes killed 553 people in 2011, but just 70 in 2012.Full Answer >