Tornadoes happen when certain atmospheric conditions are met, mainly during severe thunderstorms. They typically develop from supercell thunderstorms, which have a rotating updraft called a mesocyclone. Warm, moist, unstable air rises and meets cool, dry air, creating wind shear — winds blowing at different speeds or directions at different altitudes. This causes a horizontal spinning effect in the lower atmosphere that can be tilted vertically by the thunderstorm’s updraft. When this spinning column of air intensifies and extends downward, it forms a funnel cloud. When the funnel cloud touches the ground, it becomes a tornado, capable of extremely strong winds and destruction. In summary, tornadoes occur because of:
- Warm, moist air meeting cool, dry air creating instability,
- Wind shear causing rotation of air within thunderstorms,
- A rotating updraft (mesocyclone) in supercell thunderstorms,
- A funnel cloud reaching the ground, becoming a tornado.
