Amazing Tornado Facts !
Tornadoes are one of the most dangerous storms on the planet. The are very rare and extremely unpredictable. They form out of low severe clouds called Cumulonimbus clouds. Sometimes tornadoes are accompanied by other forces such as hail and heavy rain. The damage of a tornado can be catastrophic. That is why a scientist named Dr. Theodore Fujita created a scale to measure the damage of a tornado. That scale is called The Fujita Scale. It always is used after the storm passes. It starts out at EF0 (40-72 mph. winds) and ends with EF5 (200+ mph).
Tornadoes usually form in the summertime in a place called Tornado Alley. That is where warm, moist air from the South meets cold, dry air from the north. Then all of that air mixes together and makes a thunderstorm. Occasionally that thunderstorm will turn severe. If that storm has all of the right ingredients it could make a tornado.