Formation of the Storm
Tornadoes can form in any situation that produces server weather, including cold fronts, squall lines, and tropical cyclones. The most intense tornadoes are those that form in association with super cells. An important precondition linked to tornado formation in server thunderstorms is the development of a mesocyclone. A mesocyclone is a vertical cylinder of rotating air, typically about 3 to 10 kilometers across, that develops in the updraft of a server thunderstorm. The formation of this large vortex often precedes tornado formation by 30 minutes or so.