Thunderstorm

A storm cloud appears in the shape of a cylinder that is 50 feet tall with a 200-foot radius, centered on a point you can see within range directly above you. The spell fails if you can’t see a point in the air where the storm cloud could appear (for example, if you are in a room that can’t accommodate the cloud).

When you cast the spell, choose a point you can see under the cloud. Up to three large bolts of lightning flash down from the cloud to points of your choosing. Each creature within 10 feet of those points must make a Dexterity saving throw. A creature takes 3d10 lightning damage on a failed save, or half as much damage on a successful one. On each of your turns until the spell ends, you can use your action to call down lightning in this way again, targeting the same points or different ones. A creature in the area of more than one bolt is affected only once.

After failing a Dexterity saving throw, the target(s) must then make a Wisdom saving throw. If that saving throw also fails, the target is paralyzed until the start of the casters next turn.

If you are outdoors in stormy conditions when you cast this spell, the spell gives you control over the existing storm instead of creating a new one. Under such conditions, the spell’s damage increases by 2d10.

The bolt of lightning is so strong, that there is a small explosion at the sight of the bolt. The surrounding 15 feet is considered difficult terrain from then on.