As you hold your arms out wide and hands with fingers spread, a thin sheet of flames shoots forth from the outstretched fingertips of one hand, while a sheet of ice shoots forth from the other.

This spell creates two separate 15 foot cones originating from the caster: One cone dealing Fire Damage, the other dealing Cold Damage. Each creature in a 15-foot cone must make a Dexterity saving throw. A creature takes 3d6 of the designated damage on a failed save, or half as much damage on a successful one. The Two cones created in this manner cannot intersect.

The caster can, however, choose to combine both cones into a single 30 foot cone originating from the caster. Each creature in a 30-foot cone must make a Dexterity saving throw. A creature takes 3d6 Fire Damage and 3d6 Cold Damage on a failed save, or half as much damage on a successful one. 

The fire ignites and 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 4th level or higher, each of the damage types increases by 1d6 for each slot level above 3rd.