When I mix the sky, there are often two tones, a warm and a cool, the cool will usually have a blue and a red, and maybe some muddy paint, but just a trace, the warm might have a yellow, and a touch, just a tiny touch of the mud too. I find the right color by mixing, comparing with nature, and changing the color, I've mixed enough sky, and I've kept my pallet fundamentally the same, so, I can at least start in the ball park of what I want.
I chose the scene for the dramatic and dark shadow raking across the foreground.
Here is where I finished.
There are sculptures all over the place, maybe I'll paint some.
Tomorrow my van is in the shop, so I'll paint around here and make more panels.