What You Need to Know About How Tornadoes Form
Tornadoes only form when a thunderstorm has a particular combination of winds. Air rising in thunderstorms can begin to spin when it's affected by winds blowing it in different directions. It starts to rise and is pushed to the side by wind. It rises a bit more and is jostled again by wind moving in another direction. A supercell, unlike a regular ole thunderstorm, contains the most-important ingredient in the making of a tornado: a spinning column of air at its center, called a vortex. As a supercell grows in size, the vortex in the middle will begin to tilt, siphoning warm air and moisture upward and spewing out cold dry air toward the ground.
However, when they move away from the average, tornadoes are considered tognado of the most-destructive weather events in the world. The wildest of tornadoes can last for hours and span miles in diameter, reaching up to miles km per hour in speed. In order to be prepared for these powerful twisters, meteorologists scientists who study atmospheric weather patterns have spent decades investigating the causes of tornadoes.
While the exact conditions are different for each, in order to understand how a tornado forms, we must first understand the yow that is essentially its parent—the supercell thunderstorm. A supercell, unlike a regular ole thunderstorm, contains the most-important ingredient in the making of a tornado: a spinning column of air at its center, called a vortex. Tronado a supercell grows in size, the vortex in the middle will begin to tilt, siphoning warm air and moisture upward and spewing out tornadp dry air toward the ground.
The updraft of warm air causes the vortex to swell with water vapor, creating a spiraling funnel cloud at its center—the first visible sign that a tornado is how do a tornado form. With frm pressure and weight from the downdraft of cool air, the quickening funnel cloud is forced to touch down on so ground, and a tornado is officially born. By understanding the signs of a tornado in the making, meteorologists can issue warnings and signals to areas that might soon become a little too familiar with how to cover furniture with wallpaper. Weather- surveillance systems such as Doppler radars use a technology similar to echolocation that reflects pulses off water vapor in the air to record the speed and movement of a storm.
These systems allow scientists to detect the telltale spiraling of supercell thunderstorms long before a funnel cloud is ever seen. Home Demystified Science. Jonathan Hogeback Editorial intern, Encyclopaedia Britannica.
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Sep 25, · How Tornadoes Form Tornadoes are usually born from thunderstorms. High intensity tornadoes form from supercell thunderstorms, a storm that has a “ .
Heavy, dark clouds hang low, dumping buckets of rain and hail. Suddenly, a twisting column of gray drops from the bottom of the cloud. For a while it hangs suspended in the sky. Then it extends to the ground. When it touches, it goes even darker as its ferocious whirling winds pick up dust, debris, and—if the windspeeds are fast enough—cows, cars, roofs, mobile homes, trees, and anything else not well-anchored in the ground. What makes a cloud create one of these powerful assaults to Earth's surface?
How is it that a violent whirlwind can form in a cloud and then reach to the ground and make splinters and chaos of everything in its path? On average, the U. A ten-state area of the Midwest has been named "Tornado Alley" in recognition of its attractiveness to tornadoes. However, tornadoes can occur in any state. In , Alabama was struck particularly hard, with tornadoes rated EF-5 the most intense on the Enhanced Fujita scale hitting Hacklesburg and Birmingham.
Imagery from GOES enabled weather forecasters to foresee the trouble that was about to hit Alabama. Click image for animation. With most weather events, even hurricanes, you know what to expect. The weather forecast will give you a few hours' warning and some idea of what is coming.
This information is thanks partly to hard-working satellites that keep a constant eye on the weather. However, predicting tornadoes precisely is a different story. One minute it's just raining or hailing, and the next minute the roof or even the whole house is gone.
If you were lucky, you and your family had a few seconds to find some shelter where you would not be picked up by the violent winds or seriously injured by large chunks of flying debris. Where do these violent and unpredictable storms come from? Why do they destroy some buildings, but leave others nearby untouched?
And is there any way weather forecasters could give people right in their path a little more warning? Certain conditions make tornadoes more likely. So, in that way, they are somewhat predictable.
But no one ever knows when, where, how intense, and how many tornadoes a thunderstorm will create. Conditions are ripe for tornadoes when the air becomes very unstable, with winds at different altitudes blowing in different directions or at different speeds—a condition called wind shear. The first result is a large thunderstorm. Inside the huge thundercloud, warm and humid air is rising, while cool air is falling, along with rain or hail. All these conditions can result in rolling, spinning air currents inside the cloud.
Although this spinning column of air starts out horizontal, it can easily go vertical and drop down out of the cloud. When it touches the ground, it's a tornado. The winds inside the spinning column of some tornadoes are the fastest of any on Earth. They have been clocked at over miles per hour! Sometimes the spinning column of air lifts off the ground, then touches down again some distance along its path.
It's hard to measure the winds in a tornado directly. So they are evaluated by the amount of damage they do. Here is a scale meteorologists use to describe tornado intensity based on damage.
These satellites can more quickly monitor the motion of clouds to identify a severe storm as soon as it develops. They are also better at understanding what's actually going on inside the cloud: what characteristics the cloud has that indicate a severe storm and how much lightning it produces.
All these measurements affect how likely the cloud is to produce a tornado. GOES-R series satellites will be better at seeing what's actually going on inside the cloud: how much lightning it produces, cloud top properties and the motion of the clouds. All these measurements affect how likely the cloud is to make tornadoes, and what kind of tornadoes it could produce.
Hide Subjects Browse by Subject. The Short Answer:. A tornado forms from a large thunderstorm. Inside thunderclouds, warm, humid air rises, while cool air falls--along with rain or hail. These conditions can cause spinning air currents inside the cloud. Although the spinning currents start out horizontal, they can turn vertical and drop down from the cloud--becoming a tornado.