The worst type of tornado hasn't hit the US for over a decade, perplexing experts
Researches found little evidence that tornadoes were getting weaker. Instead, it appears that a subjective tornado grading ...
South Dakota experiences first ever February tornado, rated EF-U
A recent tornado in South Dakota was given the relatively rare designation of EF-U due to the area in which it touched down.
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The worst type of tornado hasn't hit the US for over a decade, perplexing experts
Tornadoes are classified on the Enhanced Fujita scale, which ranges from EF0 to EF5. Originally created by famed tornado researcher Ted Fujita, the scale takes into account estimated wind speeds ...