@etcmike, In my opinion nowadays nature became more expressive, and these colours are telling that aspect effectively.
And literally I've never seen these Blue clouds and that's why I've said nature is becoming expressive and it's expanding it's Art.
And at the same point of time in the sky we can see so many faces of nature and it reflects as nature is applying great colour Collaboration.
And in my opinion nowadays we can see lot of changes in nature and one of the changes is reflecting by the clouds.
Wishing you an great day and stay blessed. 🙂