Strong tornadoes can have a course up to 100 kilometers long and 500 meters wide, and they can last for more than 2 hours. The rarest tornadoes are those with either a F4 or F5 rating. These events have wind speeds between 333 to 513 kilometers per hour and are very destructive and violent. Fujita tornado intensity scale. Damage is light.
Damage is severe.
Tornadoes occur in many parts of the world. Some notable hots spots include South Africa, Australia, Europe, New Zealand, northern India, Canada, Argentina, Uruguay, and the United States. Of these locations, the United States has some specific regions within its boundaries that have an extremely high number of events per year. Figure 5t-8 describes the spatial distribution of tornado frequency in the United States. Average number of tornadoes per year in the United States.