Rainbows at the library

I went downstairs to buy a soda in the breakroom about 7:45 tonight. When I got back upstairs the downpour from earlier was now a steady rain. Looking out the windows behind the reference desk there was no rain, just dark steady-moving clouds. Sitting at the reference desk and looking across, out the windows opposite, I could see a golden rain lit by the sunset. I thought that there must be a rainbow in these conditions. I looked back out the windows behind the reference desk and, sure enough, a half rainbow arcing out of the trees and to the left out of sight. It's nice to have windows at work.