It's lovely cycling before sunrises particularily during warm weather season. Just make yourself as visible as possible and not surprise any equally early drivers either.

I used to daily cycle about 40 min. before sunrise through a tall-tree forest park before starting work. Initially it was abit creepy and strange but still nevertheless exhilerating. It was on paved roads so no need to stop. It felt quite safe.

We've had to cycle off for 40 kms. starting at 4:00 am to get to airport, ferry dock..in order to catch our next ride. So peaceful.
Or to avoid high heat/humidity..but for this latter reason where we live now, less of a need.

And yes, I have done this sort of stuff in..rain. Now, that is the hardest.