There has been a lot of progress made recently with volumetric clouds in games. The folks from Reset have posted a great article regarding their custom dynamic clouds solution, Egor Yusov published Real-time Rendering of Physics-Based Clouds using Precomputed Scattering in GPU Pro 6, last year Andrew Schneider presented Real-time Volumetric Cloudscapes of Horizon: Zero Dawn, and just last week Séb