Tempest Fury

You call forth the wrath of the sea and sky, conjuring a localized miniature storm. Choose a point you can see within range. A 20-foot radius cylinder of swirling wind, rain, and lightning descends from above. Each creature in the cylinder must make a Dexterity saving throw. On a failed save, a creature takes 6d6 lightning damage and 6d6 thunder damage and is knocked prone. On a successful save, it takes half as much damage and is not knocked prone. The area then becomes lightly obscured until the start of your next turn.