Fire rainbows are the rarest of all naturally occurring atmospheric phenomena. For a fire rainbow to occur, cirrus clouds must be feet in the air with the precise amount of ice crystals, and the sun must hit the clouds at 58 degrees. (a/k/a Sun Doggies)
Tunnel View Lookout in Yosemite. Photographer Justin Lee of British Columbia said, "The sun has to be in position to get the rainbow, and this photo was not planned by me beforehand. I just happened to be in the right place at the right time.