Blizzard

An abundance of snow starts falling in a cloud within range. The area of the cloud consists of up to fifteen 10-foot Cubes, which you arrange as you like. Each Cube must be contiguous with at least two other Cubes.The area of the cloud is heavily obscured and is difficult terrain. At the start of each or your turns, each creature and plant of your choosing in the area makes a Constitution saving throw, taking 10d6 Cold damage on a failed save or half as much damage on a successful one. 

At the end of each of your turns, you may move 3 cubes to a different point within range, following the rules for placement.