A supercell is a type of thunderstorm. Supercell thunderstorms have an intense rotating updraft. This rotating updraft is known as a mesocyclone. Supercell thunderstorms often produce large hail and tornadoes. Large hail is created by the very strong updraft of a supercell. The updraft is strong enough to keep water suspended aloft in the storm. This causes the water to freeze. As it starts to drop, it is caught in the updraft and sent back up into the storm. This repeats several times until the hail stone is too large for the updraft to keep aloft.
It takes a thunderstorm to produce a tornado. Thunderstorms are created when cold dry air from the north interacts with warm moist air from the Gulf of Mexico. Warm moist air rises as the cold dry air sinks. This can help create atmospheric instability.
Some tornadoes are formed from supercell thunderstorms. It is known that there is air underneath the storm that is rotating horizontally. When the updraft of the storm strengthens, with the help of inflow winds, the horizontal rotating air can be tilted into the vertical. If the rotation is strong enough, a lowering from the base of the storm cloud can form and make a wall cloud. Sometimes, the wall cloud can be rotating as well.If the updraft, downdraft, and rear flank downdraft are present, this can strengthen the rotation and can create a funnel cloud. If the rotation remains strong and eventually reaches the ground, then a tornado has formed.