Get This Blender Add-On for Realistic Real-Time Procedural Sky

Physical Atmosphere² updates clouds, atmosphere, and lighting instantly in the viewport and has an advanced mode for precise control. Physical Addons has introduced Physical Atmosphere² , a Blender tool for creating skies with photorealistic clouds, planets, the moon, eclipses, and more. The tool uses procedural volumetric clouds that render in real time. The tool has four procedural cloud layers, and each can be customized. Users can move a slider and see the clouds change right away. The atmosphere and lighting also update instantly in the viewport as you work.