Elemental Weapons

 Choose up to three allies within 30ft of you,  the chosen creatures must be wielding a weapon.  For ten minutes or until the spell ends, each attack made with that weapon deals additional elemental damage (fire, lightning, cold, or acid) equal to 1d6  

At Higher Levels. When you cast this spell using a spell slot of 3rd level or higher, damage goes up 1d6 per level above 2.