The odds are that they will hit open land more often than cities because there is a lot of open land. Also, some of the most built-up parts of the U.S. such as the Northeast Coast and along the California Coast are places where strong tornadoes are rare because the general weather conditions aren't as favorable as they are in the Southeast, on the Plains and in the Midwest. The most violent tornadoes , F4s and F5s on the Fujita tornado intensity scale , often spawn multiple vortices while spiraling around a central axis of the parent tornado's vortex. Multiple vortices are very rare in F1-F3 tornadoes. The individual vortices in a multiple vortex tornado are indeed called suction vortices.
Scientists use the words to describe two different weather phenomena.
These include hurricanes, winter storms and tornadoes. Our tornado information index has a lot of information on what tornadoes are. In fact, no one should think of trying to chase storms without learning a lot about them. One of the links you'll find here is to the storm chasers home page, which you'll probably want to look at regularly. The best way to become a chaser is by studying meteorology in college and becoming part of a team with scientists.