They are generally not as strong as those in the United States. Tornadoes outside of the U.S. stronger than F2 are rare. However, a number of F4 and possibly some F5 tornadoes have occurred on other continents.
Tornadoes can probably occur in any country as any place that can get thunderstorms can get tornadoes.
Yes, some strong tornadoes create brief satellite tornadoes that circle the main funnel.
No, tornadoes can occur in many countries around the world. The United States experiences the most tornadoes annually, but other countries like Canada, Argentina, Bangladesh, and Australia also have tornadoes.
There were 1265 tornadoes in the U.S. in 2005. Statistics for other countries are unavailable.
Usually one tornado does not result in other tornadoes. Some strong tornadoes can produce a satellite tornadoes that orbit them, but this is not very common.
The U.S. certainly records more tornadoes than any other place in the world and is also more prone to strong tornadoes. However, many countries do not keep records of the tornadoes that they get and so the majority of the world's tornadoes go undocumented. But until more complete documentation can be established the U.S. will hold its status as the most tornado prone country.
There were 1,133 tornadoes recorded in the U.S. in 1990. Other countries have not published tornado statistics.
Tornadoes are most common in the U.S. They are poorly documented in many other countries.
Tornadoes occur in other countries besides the US. However, the US heartland has ideal conditions for tornadoes.
Big tornadoes are usually strong, but not always. A large, poorly organized tornado is not likely to be very strong. Some tornadoes even weaken as they expand.
The U.S. experienced 1374 confirmed tornadoes in 2003. Data for other countries is not available.
In the United States, strong tornadoes, counted as those rated F2 or higher, account for about 11% of all tornadoes.