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Tornadoes
A tornado or twister is a violent, rotating column of air which typically has a speed ranging from 177 km/h to over 480 km/h. This devastating windstorm is usually characterized by its funnel-shaped cloud that extends toward the ground.
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Tornadoes are typically carried along by the storm's updraft. The combination of the storm's rotating updraft and wind shear can cause a tornado to move in various directions, including forward, backward, and even in loops. The movement of a tornado can also be influenced by local topography and wind patterns.
Does wind or water cause more damage in a tornado?
Tornadoes form in unusually violent thunderstorms when there is sufficient (1) instability and (2) wind shear present in the lower atmosphere.
Instability refers to unusually warm and humid conditions in the lower atmosphere, and possibly cooler than usual conditions in the upper atmosphere. Wind shear in this case refers to the wind direction changing, and the wind speed increasing, with height. An example would be a southerly wind of 15 mph at the surface, changing to a southwesterly or westerly wind of 50 mph at 5,000 feet altitude.
This kind of wind shear and instability usually exists only ahead of a cold front and low pressure system. The intense spinning of a tornado is partly the result of the updrafts and downdrafts in the thunderstorm (caused by the unstable air) interacting with the wind shear, causing a tilting of the wind shear to form an upright tornado vortex. Helping the process along, cyclonically flowing air around the cyclone, already slowly spinning in a counter-clockwise direction (in the Northern Hemisphere), converges inward toward the thunderstorm, causing it to spin faster. This is the same process that causes an ice skater to spin faster when she pulls her arms in toward her body.
Other processes can enhance the chances for tornado formation. For instance, dry air in the middle atmosphere can be rapidly cooled by rain in the thunderstorm, strengthening the downdrafts that are needed for tornado formation. Notice that in virtually every picture you see of a tornado the tornado has formed on the boundary between dark clouds (the storm updraft region) and bright clouds (the storm downdraft region), evidence of the importance of updrafts and downdrafts to tornado formation.
Also, an isolated strong thunderstorm just ahead of a squall line that then merges with the squall line often becomes tornadic; isolated storms are more likely to form tornadoes than squall lines, since an isolated storm can form a more symmetric flow pattern around it, and the isolated storm also has less competition for the unstable air which fuels the storm than if it were part of a solid line (squall line) of storms.
Because both instability and wind shear are necessary for tornado formation, sometimes weak tornadoes can occur when the wind shear conditions are strong, but the atmosphere is not very unstable. For instance, this sometimes happens in California in the winter when a strong low pressure system comes ashore. Similarly, weak tornadoes can occur when the airmass is very unstable, but has little wind shear. For instance, Florida -- which reports more tornadoes than any other state in the U.S. -- has many weaker tornadoes of this variety. Of course, the most violent tornadoes occur when both strong instability and strong wind shear are present, which in the U.S. occurs in the middle part of the country during the spring, and to a lesser extent during fall.Interesting facts:TORNADO COUNTRY The United States experiences more tornadoes than anyplace else in the world. A few other countries that experience especially violent tornadoes include India, Bangladesh, and Argentina. It is estimated that over 95% of all tornadoes spin cyclonically (counter-clockwise). Oddly, the very first recorded video of a tornado was of one that was spinning in the otherdirection(!)
Does a skyscraper stop a tornado?
No, a skyscraper cannot stop a tornado. Tornadoes are extremely powerful natural forces that can cause significant damage to structures, including skyscrapers. However, a well-designed and sturdy skyscraper may be able to withstand some of the impacts of a tornado.
Why does a tornado have to touch the ground to be a tornado?
By the meteorological definition a tornado extends from cloud base to the ground. If it does not, it cannot produce damage. However, just because the visible funnel doesn't touch the ground doesn't mean the strong winds don't. It is the vortex of wind which defines a tornado, not the funnel.
What is the most destruction a tornado causes?
These extremely powerful winds can cause much damage, but if there is not much property at the locale, nor many people, the effects will be minor.
Thus, Bangladesh has had a tornado that caused about 1300 deaths, and another with 700 odd deaths.
Tropical cyclones have a similar general origin, and have caused even greater loss of life and property. These additionally, may have a rise of sea induced, and this also causes much damage and loss of life.
Is an EF5 tornado more powerful than an F5 tornado?
No, EF is for Enhanced Fujita scale and F is for Fujita scale. The new scale, implemented in 2007 is more accurate, but ratings are essentially equivalent. Most tornadoes would receive the same rating on either scale.
How big and how fast can the wind speed of a F6 tornado be?
The F6 category is purely theoretical. Because Fujita scale ratings are based on damage rather than directly on wind speed, there is no room for a level hihger than F5.
Now that that point is made, the theoretical range of F6 winds is 319-379 mph.
What causes a tornado to lose its strength?
A tornado can lose its strength when it moves over cooler water or land, or if it encounters strong winds that disrupt its circulation. Additionally, if the thunderstorm that spawned the tornado weakens or dissipates, the tornado will also lose strength.
What determines a tornado's EF rating?
A tornado's Enhanced Fujita (EF) rating is determined based on the estimated wind speeds and damage caused by the tornado. The rating takes into account the extent of damage to structures, vegetation, and other objects along the tornado's path. The EF scale ranges from EF0 (weakest) to EF5 (strongest), with wind speeds increasing with each higher rating.
How fast are winds in F2 tornado?
Between 113-157 miles per hour. However, the upper end of this wind estimate was found to be too high for F2 damage and so EF2 winds on the more accurate Enhanced Fujita scale are estimated at 110-135 mph.
What is the safest corner of the room during a tornado?
The safest corner of the room during a tornado is typically an interior room on the lowest level of the building, away from windows and exterior walls. Seek shelter in a small, windowless, and centrally located area like a bathroom or closet.
How are tornadoes and thunderstorms similar and different?
They are the same because they both are classified as storms and can cause damage via wind. They are different because a thunderstorm does not have a funnel of wind like a tornado. A tornado itself does not produce rain or lightning, but the thunderstorm that spawned the tornado can. Also, the winds in a tornado are more violent than those just caused by a thunderstorm.
Tornadoes form when there is a change in wind direction and speed along with atmospheric instability. This creates a rotating column of air extending from a thunderstorm to the ground, causing the tornado to touch down and form.
Theoretical winds for an F6 tornado are 319-379 mph. However, because tornado ratings are based on damage, the highest a tornado could ever be rated is F5. So the F6 rating is purely theoretical with no applications in the real world. On the enhanced scale there is no EF6 level theoretical or otherwise.
What kind of tool do a scientists use when they want to figure out how strong a tornado is?
Usually scientists do not use any tool to determine how strong a tornado is. Usually the strength of a tornado is determined based on the severity of damage it causes.
Occasionally wind speed measurements are obtained using Doppler radar, but such measurements are rare.
What is the most common strength for a tornado?
The most common strength for a tornado is EF0 or EF1 on the Enhanced Fujita Scale, which corresponds to wind speeds of 65-110 mph. These tornadoes are relatively weak and typically cause minor damage.
Why do you think a tornado is more dangerous on a flat plain rather than a hilly area?
Tornadoes on flat plains have fewer obstacles to slow them down, allowing them to build and maintain their intensity. In contrast, hilly areas can disrupt the tornado's circulation, potentially weakening it. Additionally, tornadoes on flat plains can cover more ground and stay on the ground for longer periods, increasing their destructive potential.
Can a tornado pick up heavy things?
Yes, tornadoes can pick up and carry heavy objects such as vehicles, trees, and large debris. The strong winds within a tornado are capable of generating enough force to lift and move heavy objects over great distances.
What feature on a weather map is most likely to be associated with tornadoes?
An area of low pressure, also known as a low-pressure system, is most likely to be associated with tornadoes on a weather map. Tornadoes often form within the intense thunderstorms that develop along the boundary of a low-pressure system.
Air and debris spin inside a tornado. The strong updrafts and rotation of the storm system can lift and move large objects, such as trees and even vehicles.
Yes. Even very weak tornadoes will lift dust and twigs. Stronger tornadoes can lift roofs, garages, barns, and some vehicles. The most violent tornadoes will lift large trucks, train cars, and even well built houses.
No, tornadoes cannot be defused. Tornadoes are powerful natural phenomena that form due to specific weather conditions, and they cannot be controlled or prevented. Safety measures such as having a plan in place, seeking shelter, and following evacuation orders are recommended in the event of a tornado.
What did tornadoes sound like before trains were invented?
Before trains were invented, people described the sound of tornadoes as similar to a roaring wind or a freight train. The comparison to a train became more common as trains themselves became a familiar and dominant source of noise in many areas.
What is the average speed that a tornado travels on the ground?
Tornadoes typically move at speeds between 25-40 miles per hour (40-64 km/h) but can reach higher speeds up to 70 mph (113 km/h) in some cases. The speed can vary depending on the specific tornado and its surrounding conditions.
Why can't tornadoes last near water?
Tornadoes tend to weaken and dissipate quickly over water because the unstable air needed to sustain them is not as readily available as it is over land. The cool and moist conditions over water are not conducive to maintaining the circulation and strength of a tornado.
