Tornado uses a large mist generator, fans and a care fully-shaped structure to produce a large tornado. Since the Exploratorium first produced this crowd-pleasing exhibit, it has been duplicated in many museums. Our fourth generation version is intentionally de-tuned so that random air currents can cause both the creation of a tornado and its temporary cessation. This latest Tornado is chaotic and unpredictable much of the time; it wanders off the source of the mist, slips out of the grasp of the shearing winds and presents a delightful and ever-changing image.