Blizzard

A vortex of the coldest winter ravishes your enemies. 

Each creature in a 20-foot cube centered on that point must make a Dexterity saving throw. A target takes 8d6 of cold damage on a failed save, or half as much damage on a successful one.

At Higher Levels. When you cast this spell using a spell slot of 4th level or higher, the damage increases by 1d6 for each slot level above 3rd.