Twisters Untangled: Understanding Tornadoes A step-by-step guide to the development of tornadoes and a historic look at Tornado Alley.
NPR logo Twisters Untangled: Understanding Tornadoes

Twisters Untangled: Understanding Tornadoes

Tornadoes sometimes form in the midst of thunderstorms, when cold dry air meets warm, moist air. These conditions are most common in the region between the Rockies and the Appalachian Range known as "Tornado Alley".