After the moon set I noticed the white clouds, after watching them for a while it was obvious they were the noctilucent. I haven't seen them before, as it got darker it got better. I had dead batteries and no extra so missed the end of it. As it got darker the area where the last light disappears now became a blue I haven't seen in the sky before, my wife said it's called periwinkle blue. The white luminescent clouds were in it and capped it. It's just sunlight reflecting, but it appears to glow. I was able to see them beginning about 10:15 pm, but that would be later each night if they are there at all. It was best about 10:45.