Tornadoes form when hot, humid air rises from the ground and meets with the cooler, denser air that is falling back to Earth. The two airstreams begin to swirl, pulling in more and more air to form a funnel-shaped cloud. The winds can swirl faster than 261 miles per hour! Newly revised and vetted by weather experts, this book is an accessible introduction to this fascinating phenomenon. Using her praised combination of clear text and detailed illustrations, Gail Gibbons shares more than fifty tornado facts... including how tornadoes form, the scale used for classifying them, and the safest places to go in case one should happen near you. Includes updated information on the affects climate change on extreme weather and the increase of tornado activity in the American South.