Underwater light condition and view distance should change related the wheater condition but is not.
The view distance should be affected by waves, more waves less view distance, less waves more view distance. I'm living near the sea and I know what I'm talking about, I have experimented those condition personally.
The next picture will show you the underwater enviroment with 3 type of weather condition:
- Overcast 0, wind 0
- Overcast 50%, wind 50%
- Overcast 100%, wind 100%
All the picture are the same except the wave shape.
- Overcast 0, wind 0
- Overcast 50%, wind 50%
- Overcast 100%, wind 100%
In real life, the actually undewater view distance should represent a 66-75% in game Overcast, while the overcast zero should have a view distance 3 times higher.
Sometimes, in real undewater enviroments, the view distance reach 100-150 meter, and the water in like a cristal.