A player reported having this issue on the 1080Ti where meshes blending against the clouds seem hollowed out. Issue goes away if clouds get disabled.
Glad you posted this
I agree, I also have the same issue with clouds when they are low in enough to cover mountains while looking from terrain level. There is a strange outline that happens along the edge of the mountains
I also use a 1080ti presently in my development. I have not found a solution yet other than presently making sure clouds don’t cover the tops of mountains for now.