I saw in another forum that a CiC was trying to get a feel of the visibility conditions.
First of all, there is a custom cloud system that is very thick Clouds from varying altitudes to the deck. It is located mostly in the Ardennes GV base area.
The Fog Visibility will be at 12 Miles.
Custom color settings will be changed to give a more realistic overcast while keeping visibility up. The following Color settings will be changed to the listed numbers.
FogDay - 130/130/130
LightDay - 192/192/192
SkyDay - 153/153/153
SunDay - 192/192/192
Thanks to Dux and Baumer.