Where in the world can tornadoes occur and why?

Tornadoes can occur in many parts of the world but are most commonly found in the United States, particularly in a region known as "Tornado Alley," which includes states like Texas, Oklahoma, and Kansas. They form when warm, moist air from the Gulf of Mexico collides with cold, dry air from Canada, creating unstable atmospheric conditions. Other countries, such as Canada, Bangladesh, and parts of Europe and Australia, also experience tornadoes, though they tend to be less frequent and less intense. The key factors for tornado formation include specific climatic conditions and geography that promote severe thunderstorms.