We decided to take a quick look from the Rim after supper one evening. This shower came down the canyon - only lasted about 5 minutes.
The Grand Canyon is one of the most spectacular places on earth - you should visit it if at all possible. But don't go for two hours midday; to truly enjoy the colors and shadows you need to be there for sunrises and sunsets. And you want to be on the South Rim. I have a beautiful slide show I can email if you would like.