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 Magic Tree House Research Guide: Twisters and Other Terrible Storms, 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!