There are three main types of all thunderstorms:
Single-cell or your normal thunderstorm.
Multi-cell a thunderstorm that is connected to other thunderstorms.
Finally Supercell, the most dangerous and usually severe.
There are three types of severe thunderstorms.
1; baseline severe thunderstorm. Winds are 58 miles per hour or greater. Hail size 1.00 inch or greater.
2; considerable damage severe thunderstorm. Winds are 70 miles per hour or more. Hail size 1.75 inches or greater.
3; destructive damage severe thunderstorm. Winds are 80 miles per hour or more. Hail is 2.75 inches or greater.
If there is tornadic activity a thunderstorm is severe but to determine the severity scale you need to look at wind speed and hail size.
Remember all thunderstorms have lightning. Be careful when around thunderstorms.
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