Pink Rainbow

[mikfez]

Rare pink rainbow forms over East Yorkshire >

The pink appearance of the rainbow, as opposed to its typical full spectrum, comes as a result of an optical illusion and is described as a very rare phenomenon.
This happens as the red in the rainbow is refracted due to the sun being lower when is rises or sets.

Hull Daily Mail Link

 

[BS3]

Not really clouds as such, but I did see this very interesting thing a few years back: a late evening rainbow opposite the sunset, where all the usual colours were dramatically tinged pink (as usual the camera doesn't really do it justice).