Police say Christopher O'Neill was electrocuted about 11 p.m. Thursday.
Family members heard a "pop" and saw a flash when the power line fell and believed their neighbors' home might have caught fire.
Christopher, who was about 16, rushed to alert the neighbors, a family that included several young children. With electricity out in the area, he couldn't see clearly and ran into the waist-high line.
In the same county, Kent, a lightning strike set fire to a home, and heavy rain in the region flooded some roads. Consumers Energy Co. reports some 36,500 customers were without power statewide.