This is good work, but I agree with Syrupmasterz, the mountains aren't quite there with the rest of the piece for me. It feels like it's not quite finished...it's just a few details off from a higher rating for me. The mountains, and also I would have liked a little more detail on the moon so it looks like more than a gray disk.
But really, this is good work. The lightning looks fantastic, and the illuminating effects you have applied to it are perfect. I enjoy the simple palette you used here, it really works for this piece. I'd like to see this just a bit more polished, keep up the good work.