It rarely rains in the Bay area in summer time, but today we had a few scattered rain showers.

Just now, I was sitting at my desk, and happened to look up at the sky. I can’t see much of the sky from where I sit: trees and buildings limit my view. But there, in the small portion of the sky I could see, was part of a rainbow. I stepped outside to look at it. There was one small rain shower coming down from the clouds to the east — I could see the gray streaks of rain — and a little patch of sunlight just happened to light up that portion of the sky, causing a rainbow that encompassed about fifteen degrees of a complete circle.

I stood and watched it for about five minutes. At its brightest, there was the main spectrum, then immediately under it a smaller spectrum, the blue of the larger one fading directly into the red of the smaller one, and under that an even smaller spectrum. But soon the rain shower drifted out of the patch of sun, and the rainbow faded away.