Scott Westerfeld quote: “The early summer sky was the color of cat vomit.”

“The early summer sky was the color of cat vomit. Of course, Tally thought, you’d have to feed your cat only salmon-flavored cat food for a while, to get the pinks right.”

Scott Westerfeld book Uglies

Source: Uglies

“Summer came.
For the books thief, everything was going nicely.
For me, the sky was the color of Jews.”

Markus Zusak book The Book Thief

Source: The Book Thief

“The sky was the color of Edgar Allen Poe's pajamas.”

Tom Robbins (1932) American writer

“He was never loud and noisy, but calm and serene as a summer sky, and as pure.”

Frederick Douglass (1818–1895) American social reformer, orator, writer and statesman

Source: 1880s, Life and Times of Frederick Douglass (1881), pp. 263–264.
Context: I had been living four or five months in New Bedford when there came a young man to me with a copy of the Liberator, the paper edited by William Lloyd Garrison and published by Isaac Knapp, and asked me to subscribe for it. I told him I had but just escaped from slavery, and was of course very poor, and had no money then to pay for it. He was very willing to take me as a subscriber, notwithstanding, and from this time I was brought into contact with the mind of Mr. Garrison, and his paper took a place in my heart second only to the Bible. It detested slavery, and made no truce with the traffickers in the bodies and souls of men. It preached human brotherhood; it exposed hypocrisy and wickedness in high places; it denounced oppression; and with all the solemnity of "Thus saith the Lord," demanded the complete emancipation of my race. I loved this paper and its editor. He seemed to me an all-sufficient match to every opponent, whether they spoke in the name of the law or the gospel. His words were full of holy fire, and straight to the point. Something of a hero-worshiper by nature, here was one to excite my admiration and reverence. It was my privilege to listen to a lecture in Liberty Hall by Mr. Garrison, its editor. He was then a young man, of a singularly pleasing countenance, and earnest and impressive manner. On this occasion he announced nearly all his heresies. His Bible was his textbook — held sacred as the very word of the Eternal Father. He believed in sinless perfection, complete submission to insults and injuries, and literal obedience to the injunction if smitten "on one cheek to turn the other also." Not only was Sunday a Sabbath, but all days were Sabbaths, and to be kept holy. All sectarianism was false and mischievous — the regenerated throughout the world being members of one body, and the head Christ Jesus. Prejudice against color was rebellion against God. Of all men beneath the sky, the slaves, because most neglected and despised, were nearest and dearest to his great heart. Those ministers who defended slavery from the Bible were of their "father the devil"; and those churches which fellowshiped slaveholders as Christians, were synagogues of Satan, and our nation was a nation of liars. He was never loud and noisy, but calm and serene as a summer sky, and as pure. "You are the man — the Moses, raised up by God, to deliver his modern Israel from bondage," was the spontaneous feeling of my heart, as I sat away back in the hall and listened to his mighty words, — mighty in truth, — mighty in their simple earnestness.

“The sky itself is the eighth color of the rainbow, spread over the whole sky for us, all the time.”

Kim Stanley Robinson book Galileo's Dream

Source: Galileo's Dream (2009), Ch. 15, p. 354

“Summer was our best season: it was sleeping on the back screened porch in cots, or trying to sleep in the treehouse; summer was everything good to eat; it was a thousand colors in a parched landscape; but most of all, summer was Dill.”

Harper Lee book To Kill a Mockingbird

Variant: summer was our best season: it was sleeping on the back screeneed porch in cots, or trying to sleep in the treehouse; summer was everything good to eat; it was a thousand colors in a parched landscape.
Source: To Kill a Mockingbird