Sorry, gotta toot my own horn on this one. One of my very favorite websites if the Straight Dope (www.straightdope.com), a repository of wisdom and, well, straight dope. Anyway, I had the fortune a while back to have had my question picked out from what must be a kajillion questions daily and posted on the site: Are UV Rays Really More Powerful on Cloudy Days? (http://www.straightdope.com/columns/read/2732/are-uv-rays-really-more-powerful-on-cloudy-days)
I'd like to note one mistake: the "when I asked a friend" part should read "when I asked my girlfriend", for this was a conversation that my former girlfriend Keiko and I would have, so it was Keiko that inspired this question. I like to give credit where credit is due.
Anyway, enjoy!
