Best thing about this is that the clouds(although not many are there) the way i have it set up if you open the psd the cloud layers can be moved around or copied.
Clear blue skybox (tested in Unity 3D)
There is no sun, so a rotating sun can be implemented in a game engine with use of flares for example.
There are a few clouds to add detail and keep it looking interesting but i tried to keep it minimal so that more clouds can be added for maybe a stormy sky.
All textures 2048 x 2048 and match up seamlessly.
Great for games!