Cool, clear morning and quite dark at 7am when I left for work. I like to think that my flashing lights make me more visible - or at least seen sooner - when it's dark than during the day.
I wore my neon green jacket and when I was walking into the office, a coworker said, "You look like a highlighter!" Ha ha! Another guy who rides or used to or something said, "It's good to be visible when biking."