This basic horizon front view shot is going to be an alien landscape or a fantasy landscape, it depends on what you want. However, for the description, it will be alien cause its more fun to ask why instead of having faith in magic. So with my limited knowledge of the universe I would like to explain this image.
The rivers are parts of water and methane on a planet orbiting a dwarf star. The dwarf star gives it the darker appearance due to its lack of brightness, which causes the water and the distant sky to seem dim. This image is at a perfect High Noon, due to the absent of shadows, and the dark blue that appears closer to the horizon. This shot takes place in a valley, just behind mountains that would usually block all the wind that is rushing from the other side. Years of wind corrosion is causing the mountain to thin out at the peaks.
I have no idea how to explain the clouds. I thought they looked cool. The explanation isn’t perfect, mostly because I doodled this first, then tried to make the science fit what I already came up with… which in itself is an act I find disgusting in the main stream of thinking.