SceneCity comes with SceneSkies, a separate Blender addon.
It contains ten super realistic panoramic skies. Each sky is 8000x4000 pixels, for highly detailed clouds. They're also pure HDRs in 16bit EXR format.
The skies give realistic lighting extremely easily (basically in one click) AND they react properly with color grading and exposure settings in Blender. The sun is as bright as the sun in real life (thousand times stronger than a car's headlights), giving sharp and strong shadows under clear weather conditions.
