Science
What is Tornado?
A tornado is a violently rotating column of air that reaches from a thunderstorm down to the ground. Though small compared with a hurricane, a tornado packs the fastest winds on Earth and can destroy almost anything in its narrow path.
See it, don’t just read it.
Watch a 2-minute lesson with voice + animation that explains tornado.
Key things to understand
- 1Tornadoes form from powerful thunderstorms when warm, moist air meets cold, dry air and winds set the air spinning.
- 2A rotating updraft can tighten into a funnel; when it touches the ground, it becomes a tornado.
- 3They're usually a few hundred metres wide and last minutes, but the strongest have winds over 480 km/h.
- 4Strength is rated on the Enhanced Fujita (EF) scale, EF0 to EF5, based on the damage caused.
- 5'Tornado Alley' in the central United States sees more tornadoes than anywhere else on Earth.
Frequently asked questions
- What's the difference between a tornado and a hurricane?
- A tornado is small and short-lived, forms over land from a thunderstorm, and can have the fastest winds on Earth. A hurricane is vast, forms over warm oceans, and lasts for days.
- How are tornadoes measured?
- On the Enhanced Fujita (EF) scale from EF0 to EF5, which estimates wind speed from the damage left behind rather than measuring it directly.
- Where do tornadoes happen?
- They can occur on most continents, but are most common and intense in the central US ('Tornado Alley'), where the right air masses regularly collide.