Thunderstorms are storms that generates lighting and thunder, they are caused by warm, unstable air. They produce heavy winds, heavy rain and hail. They form when warm, wet air rises and they have 3 stages on how they form. The first stage is Cumulus Stage. Cumulus stage is when the air rises and the clouds grow bigger. The second stage is the Mature Stage. That's when the cloud is at it's biggest, has a large amount of water, and precipitation occurs. Last but not least the last stage Dissipating Stage. The dissipating stage is the ending of the thunderstorm. It's when the precipitation cools the cloud down and the storm dies. Storm last for 1-2 hours.
Tornadoes are violent winds storms that forms a vortex. A vortex is a rotating column of air that comes from a very large cloud (called cumulonimbus cloud). A tornado is formed when a thunderstorm begins and warm air rises. Next the warm air begins to rotate (called a mesocyclone). Then the air begins to roll creating a vortex. An interesting fact is that a tornado strength is measured using the Fujita Scale.
Hurricanes are the most violent storms on Earth. They get their strength from water in the ocean. They can also be called typhoons and cyclones. They are formed when there is a thunderstorm but they must have warm water temperatures that creates warm/moist air. Next warm air from storms move to the center and rises creating clouds, from that the cloud forms a ring called the eye wall. The ring then spins and grows, but once the storm hits land it dies. Similar to the tornado a hurricane also has a damage scale called Saffir-Simpson Scale.