The clouds are stock, but the weather engine, that is generating this cloud formations, is not official. is still beta (use at your own risk) and is only available in full mission builder.
It is somewhat buggy, not optimised and bigger cloud formations, with turbulence and and stuff are chocking the life out of my computer.:lol:
In the mission builder, if you click on objects, you can select from that drop down menu "Local weather".
I just placed three clouds on the map. extended the size much further away, by adding two zeros in the firs two boxes and I placed them one at 600m, the second at 3000m and the third layer at 4000m altitude. Then i played a bit with the density and winds in that menu.
You can get realy creative with that weather engine but it tends to crash from time to time, and it doesn't always want to do what you want.
When will be ready and official, with new cloud textures, it should be a very powerful tool.
