A tornado is a rapidly rotating column of air that extends from a thunderstorm cloud to the ground, causing violent winds and destruction. Tornadoes form when warm, moist air near the ground meets cold, dry air aloft, creating conditions that make air spin horizontally, which is then tilted upright by updrafts in the storm.
What is a Tornado
A tornado is a violently rotating column of air that forms under a thunderstorm and extends from the cloud base down to the ground. It is one of nature's most destructive weather phenomena. Tornadoes can destroy buildings, uproot trees, and create winds stronger than any other weather event. They can occur anywhere but are most common in the central United States, an area called Tornado Alley.
How Tornadoes Form
Tornadoes develop under specific atmospheric conditions. When warm, moist air from the surface meets cold, dry air high in the atmosphere, it creates instability. As warm air rises rapidly in an updraft, it creates spinning motion. Wind shear, which is a change in wind speed or direction with height, tilts this spinning motion from horizontal to vertical. When this vertical spinning column of air extends down and touches the ground, a tornado forms.
Tornado Structure
A tornado has three main parts: the mesocyclone, which is the rotating column of air in the parent thunderstorm; the funnel cloud, which is the visible rotating cloud extending downward; and the damage path on the ground. The center of a tornado, called the eye, can sometimes have relatively calm conditions, similar to a hurricane's eye. The strongest winds occur just outside this center.
Tornado Damage and Effects
The extreme winds in a tornado can destroy almost anything in their path. Buildings can be reduced to rubble, trees can be snapped like toothpicks, and objects can become dangerous projectiles. Tornadoes can also cause secondary damage through lightning, hail, and heavy rain. The damage path shows where the tornado touched the ground, and areas outside this path may experience little to no damage.
Tornado Classification and Safety
Tornadoes are rated on the Enhanced Fujita Scale, which ranges from EF0 (weakest) to EF5 (strongest), based on the damage they cause. The safest place to be during a tornado is in a basement or interior room on the lowest floor of a sturdy building, away from windows. Weather alerts and warnings help people prepare and seek shelter when tornadoes are possible or have been sighted. 
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