Acid Storm

You create a downpouring of caustic acid in a 20-foot radius cylinder within range that’s 40 feet high. While the spell lasts, creatures who start their turn in the area or enter it take 8d8 acid damage and are blinded for 1 minute. Affected creatures who roll a successful Dexterity saving throw take half damage and are not blinded. Creatures blinded by this spell can use an action to wash out their eyes if water is available, ending the condition. After the first round of the spell's duration, you can use a magic action to move the storm up to 30 feet. 

Using a Higher-Level Spell Slot. The duration increases by 1 round per spell slot level above 7th.

Adapted from the Player's Guide to Faerûn (3e).