What causes the earth's weather? How do twisters form? What are the deadliest storms on earth? Find out the answers to these questions and more in <em>Magic Tree House Research Guide: Twisters and Other Terrible Storms, </em>Jack and Annie's guide to nature's wildest weather. Includes photographs, definitions, an index, information on twisters, hurricanes, blizzards, forecasting the weather, storm chasers, and much more!