We had an unusually long rainy season here in the California desert this past winter. It was nice!
The clouds broke for an hour or so on this day, and this rainbow appeared, literally stretching from one side of the horizon to the other side.
So huge, I could not get both ends in my viewfinder.
But the colors were so bright, and the rainbow was so strong that if you look close you can see an aura above the actual rainbow.
The rainbow stayed in the sky for nearly an hour! Then the clouds came back, and it rained for another few days.