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Possible plausible hypothesis about the physical nature of the tornado funnel is the assertion that the tornado funnel is a special form of a powerful rotating flow of rain and hail coiled into the spiral-tube which then merges and forms a thin wall of conical or cylindrical shape. It’s maintained by the balance of centrifugal force, acting on the wall and the force from the differential pressure inside and outside of the funnel. The water mass in the wall of the funnel must by many times axceed the mass of the air there.