Chasing rainbows can be dangerous: this was an instance of dodging lightning strikes from the t-storm(s) rolling through while running back to the car from the view spot to get the super-wide angle lens to take this picture before the rainbow faded.
GPS location: 38°32½'N, 107°41'W; 8370 feet altitude. (guesstimated)

The native resolution of the original digital file is high (7.8 MP). This 500+ KP version for electronic display represents a reduction in area of ~16x.