I have been trying to get this working for aa few days now but cant seem to get it right. 
I have a environment scene with “snow wisps” Niagara systems that spawn from the peeks of hills to create a snow smoke effect. But they don’t render correctly to match true sky clouds. I’m using the TrueSkyTransparancy node in the material like the example material shows, but it goes totally black at night and shows through the fog/haze very clearly. I am trying to make the material blend in with the clouds themselves.