Realtime Melting Snow (UE4)

Using exposed parameters in substance designer I could make different states of snow, like how much it had melt or how windswept the snow was. 
To make that use-able in a game environment without having having all these heavy calculations, I saved multiple states by pre-calculating them and letting them blend in with masks. This also makes possible to have a localized, smooth-running and changing snow in Unreal engine. I'll try to visualize this for you by giving each mask a color in the following videos below. I'll also include the important part of the shader-nodes I used.