What happens when warm, moist air from Mexico and cool dry air from Canada collide? A tornado occurs. A tornado is a strong rotation of storm wind that reaches the ground. Tornadoes can destroy buildings, knock over trees, and move cars. Each year, there are around 1,000 tornadoes reported nationwide in the U.S.
Tornadoes can occur at any time of the day or year. Meteorologists don’t know exactly how all tornadoes form, but some of the basics remain consistent: when winds blow at different speeds and heights, they form a rotating mass of air. This mass of air rolls along the ground just like a can rolling along the sidewalk does. Then, it is pushed up-right by warm, rising air, which is called an updraft. When caught in the flow of air moving into the storm, the winds tighten and move faster. This creates a funnel cloud that moves as fast as 300 miles per hour. Rain or hail pushes the funnel cloud towards the ground, thus forming a tornado. One in one thousand thunder storms produce a tornado.
In addition to traditional tornadoes, there are many other types of windstorms such as gustnado, waterspouts, landspouts, and dust devils. A gustnado is a weak whirlwind that forms a gust of wind but does not reach the ground, wheras a waterspout is a weak tornado that occurs over bodies of water. A landspout is just like a water spout, except it occurs on land. In contrast, a dust devil is a harmless whirlwind not associated with a storm.
In northern states, tornado season is in the summer. Southern states have two tornado seasons—one in fall and one in spring. Most tornadoes in the United States occur in “Tornado Alley,” which includes Texas, Oklahoma, Nebraska, South Dakota, North Dakota, Iowa, Missouri, Arkansas, and Louisiana.
How tornadoes stop is a mystery, and researchers are still seeking to answer this question. That being said, it seems that with every tornado that swirls, researchers continue to uncover new discoveries about these lethal winds.
[Sources: www.weatherwizkids.com; UCAR Center for Science Education]