A tornado with wind speeds of 302 miles per hour (485 kilometers per hour) is difficult to even comprehend, but residents of Oklahoma experienced such a storm in 1999. Tornadoes are incredibly powerful phenomena of nature. Why are the United States and Canada the only countries to have ever experienced the strongest tornadoes? In this book, readers will get the answer to that question, and will learn about exactly what a tornado is and how one forms. Learn vital tips to staying safe in one of these monsters, and read about the deadliest tornadoes of all time. Readers will also discover what characteristics of a tornado are important to scientists, and will learn about the Enhanced Fujita (EF) scale that scientists use to measure tornado strength. Each book in the Facing the Weather series provides interesting information about storm fundamentals, history's most extreme storms, and how scientists study and predict these weather events. Readers will be amazed learning about the most extreme weather on our planet.