I don't know if this will help, but I just had a dream about why lightning flashes, and I may have an explanation. Ok, every night ever since my mom divorced, I have seen at least one lightning bolt every night for two years. I believe it is because I have lost countless loved ones. If you have too, this may be your reason. Why lightning? I examined it, and I believe that it is God telling you that if you worship him, no matter who or
where or what situation you're in, if you are with him, he will lead you out. So, I hope I helped.