# Tornado - Source: Simple English Wikipedia (simple.wikipedia.org), CC BY-SA 4.0, Simple English Wikipedia contributors - Reading level: Grades 9 and up - Subjects: Nature, Science - Topics: tornado, tornadoes, damage, scale, fujita, people - Length: 1518 words, about 11 min - Published: 2006-03-03 - Original: - Page: - Open in Sprouts: ![](https://sprout.rootsofreason.org/media/simple-wikipedia-tornado-simple-english-wikipedia-the-free-encyclopedia-9b30780f21.jpg) A **tornado** is an area of fast spinning winds made by a strong rotating thunderstorm that touches the ground. Tornadoes can be anywhere between a few hundred feet wide and several thousand feet wide. Wind inside a tornado can be intense and life-threatening, though winds outside or around the tornado perimeter can be as dangerous as the inflow. Tornadoes are life-threatening weather hazards, and heavy precipitation shafts (called the bears cage in meteorology) often obscure appropiate details like the edges of a tornado and potential multi-vortices systems. Tornadoes are especially hazardous to people in cars, trucks, buses and mobile homes. About 60 people are killed by tornadoes every year, and EF5 (F5 historically) or EF4 (F4 historically) make up many of those deaths every year. The word "tornado" comes directly from the Spanish word *tronada* (thunderstorm), which comes from the word *tronar* (to thunder). Tornadoes are very destructive – they can wipe a second-story house off of its foundation if they reach historic EF5 and EF4 wind levels. Cars and trucks may be lofted and tornadic damage often leaves many individuals financially unstable. Tornadoes are detected by visible wind rotation in an area and funnel clouds (distinct from SCUD clouds). Nearly three quarters of the world's tornadoes happen in the United States. However, they can happen anywhere. The strongest tornadoes were estimated to have winds around 300 mph, though most tornadoes have winds between 60 and 100 miles per hour. Tornadoes mostly happen during rotating thunderstorms called supercell storms. These supercells have a rotating updraft, called a mesocyclone, which can lead to them being very hazardous, often producing large and damaging hail and/or damaging winds. Tornadoes are ranked on the Enhanced Fujita scale, from EF0 to EF5. EF0 is used for tornadoes that cause the least amount of damage, and EF5 is used for tornadoes that cause the most amount of damage. Before 2007, tornadoes used to be rated on the Fujita scale, a now outdated scale made by tornado scientist Ted Fujita. Fujita was one of the first people to make detailed research on tornadoes and discovered many things about tornadoes. He made the Fujita scale in 1971. Tornadoes can happen in nearly any part of the world. In the United States, a tornado has happened in every state. The middle part of the United States is nicknamed "Tornado Alley" because of the number of tornadoes detected every year. However, many go their entire lives, usually 60–70 years, without seeing one. Other tornado-like phenomena that exist in nature include gustnadoes (not a true tornado), dust devils(categorized as a wind phenomenon), fire whirls, and steam devils; downbursts are frequently confused with tornadoes, though their behaviors are distinct. ## Characteristics ### Condensation funnel Low pressure caused by the high wind speeds and rapid rotation may cause water vapor in the air to condense into a visible *condensation funnel*. Occasionally, the condensation funnel of a tornado does not show the full size of the wind vortex. A tornado may have a small condensation funnel but still have tornado-force winds a mile away, meaning they can be extremely dangerous to people caught unprepared, including drivers and even experienced storm chasers. Funnels do not need to touch the ground to be dangerous, and this assumption takes several lives every year. Tornado family A single storm may produce multiple tornadoes and mesocyclones. Tornadoes produced from the same storm are referred to as a *tornado family*. Sometimes multiple tornadoes from different mesocyclones can be on the ground at the same time. Families like these can lead to oblong paths of damage, like with the 2021 Quad-State tornado family. (Tragically taking the lives of over 50+ people in one incident on December 10, 2021) Occasionally, tornadoes are spawned from a severe weather event spanning multiple states. If there is little to no break in their activity, this is considered a *tornado outbreak*, although there are various definitions. A period of several successive days with tornado outbreaks in the same general area (spawned by multiple weather systems) is a *tornado outbreak sequence*, occasionally called an extended tornado outbreak*. 148 tornadoes struck on the same day in April 1974. Many towns in the midwestern United States and Canada were destroyed with more than 300 people losing their lives.* ## Damage scale Tornado rating classifications | F0 EF0 | F1 EF1 | F2 EF2 | F3 EF3 | F4 EF4 | F5 EF5 | | --- | --- | --- | --- | --- | --- | | Weak | Strong | Violent | | | | | | Significant | | | | | | | Intense | | | | | The Fujita scale and the Enhanced Fujita Scale rate tornadoes by how much damage they cause. The Enhanced Fujita (EF) Scale was an update to the older Fujita scale. The updated scale uses engineered wind estimates and has better damage descriptions. The EF Scale was designed so that a tornado rated on the Fujita scale would get the same numerical rating, and was used in the United States since 2007. An EF0 tornado may damage trees, but leave most of the land intact, whereas an EF5 tornado can rip well-built buildings off their foundations leaving nothing left and even permanently damage big skyscrapers. In the United States, 80% of tornadoes are EF0 and EF1 (equivalent to T0 through T3) tornadoes. Less than 1% of tornadoes are violent tornadoes (EF4 or EF5, or equivalent to T8 or stronger). Although they account for less than 1% of tornadoes, they make up the vast majority of deaths according to weather statistics and tracking data. Due to a change in the way tornadoes were rated after 2013, no tornadoes ended up getting an EF5 rating until 2025, where a large tornado struck near Enderlin, Nebraska, sending train cars flying through the air. A survey by the Northern Tornadoes Project found that winds well above the EF5 threshold would be needed to do the damage done. ## Tornado watches/warnings/emergencies ![](https://sprout.rootsofreason.org/media/simple-wikipedia-tornado-simple-english-wikipedia-the-free-encyclopedia-5d20d92bd9.jpg) A home damaged by an F3 tornado in Forney, Texas A "tornado watch" is given when the weather conditions look like a storm capable of making tornado could form. A 'PDS (Particularly Dangerous Situation)' watch is given when a likely tornado outbreak is to start, many strong tornadoes will form in the area, or an ongoing tornado outbreak is currently occurring. A "tornado warning" is issued over a small area (usually the size of a city or a portion of a county) if meteorologists think a tornado could form or is on the ground, using radar data or if a tornado has been reported by an individual. Tornado emergencies can be issued if a likely strong or intense tornado is about to hit an area with a lot of people in it (especially cities in Tornado Alley), a tornado has been spotted, and the tornado is expected to cause deaths or severe harm. ## Myths and misconceptions It is often thought that opening windows will lessen the damage caused by a tornado. While there is a big drop in atmospheric pressure inside a strong tornado, it is unlikely that the pressure drop would be enough to cause the house to explode. Opening windows may actually increase the tornado's damage. A violent tornado can destroy a house whether its windows are open or closed. Another common misconception is that highway overpasses provide adequate shelter from tornadoes. Due to the Venturi effect, tornadic winds are stronger in the small space of an overpass. In the 1999 Oklahoma tornado outbreak of May 3, 1999, three highway overpasses were directly hit by tornadoes. At each of the three places there was a death, along with many life-threatening injuries. By comparison, during the same tornado outbreak, more than 2000 homes were completely destroyed, with another 7000 damaged, and yet only a few dozen people died in their homes. There are areas which people believe to be safe from tornadoes, whether by being in a city, near a major river, hill, or mountain, or even protected by supernatural forces. Tornadoes have been known to cross major rivers, climb mountains, hit valleys, and have damaged several city centers. As a general rule, no area is safe from tornadoes, though some areas are more likely to be hit than others. ## Safety tips To keep safe in a tornado, here are some tips people can follow: - Go to the lowest floor of the building. Stay close to the center of the building and away from windows, for example, a bathroom with no windows and get into the bathtub. - Find a piece of strong furniture or a mattress to go under or hide in a closet and wait until it is over. - If inside a school, do *not* go to the gymnasium or any other place that has a high ceiling. Squat near the wall, placing the hands on the back of the head. - If shelter is not available, find the lowest, most protected ground and cover the head with the hands. - Do not drive if a tornado may be on the ground. If a person finds themselves in their car, they should position their head above the steering wheel, and cover themselves up. Hail, high winds, and heavy rainfall may make driving very dangerous. - Do not seek shelter underneath an underpass or a bridge, as winds can increase under a bridge. ## Picture credits - Daphne Zaras, Public domain () - Matthew T Rader, CC BY-SA 4.0 ()