Blistering Sands

You summon a swirling storm of scorchingly hot sand at a point within range. The storm occupies a 15-foot cube and any creature within that area when the spell is cast, or that moves into the area or starts its turn there, must make a Dexterity saving throw. On a failed save, the creature takes 4d8 bludgeoning damage and 4d8 fire damage, taking half damage on a successful save.

As an action on subsequent turns, you can move the storm up to 30 feet. The storm can fly over barriers as tall as 10 feet and can freely float across pits, no matter how deep. 

At Higher Levels. When you cast this spell using a spell slot of 5th level or higher, both the bludgeoning damage and the fire damage increase by 1d8 for each slot level above 4th.