A large firestorm appears where you will it. You must be able to see the spot you're aiming at.  Each creature in a 50-foot-radius sphere centered on that point must make a DC 22 Dexterity saving throw. A target takes 12d12 fire damage and 4d8 force damage on a failed save, or half as much damage on a successful one.

The fire spreads around corners. It ignites flammable objects in the area that aren't being worn or carried.

At Higher Levels. When you cast this spell using a spell slot of 9th level, the damage increases by 1d12.