Messed around with it for a bit. I found it hard to notice where Storm Cell is since it likes to follow mobs and yourself like a pet. Maybe a ground indicator like the martial combat, initial reaction, ground effect but slightly minimised and reversed like the force is going outwards. I really love the snipe animation. I hope it gets proliferated but I understand it won't be for thematic reasons.
Edit: There seems to be puddles or splashes at the ground of Storm Cell