Can fog and rain help against surface vessels like it can against aircraft?

[Paul Riley]

I was just wondering about fog and rain and its effects on certain units in the game.I know that fog helps a great deal against aircraft as I have experienced no air attacks during these conditions,but against surface vessels can it also aid us?.I expect that it will of course affect his visibility,just like it does with us,and that his radar will no doubt penetrate his blindness,and that our Metox will warn us of incoming radar signals allowing us to make a dive just in time.Am I correct in thinking all this?.
If it does help in the way i'm thinking it does,it would definitely increase our range by allowing us to cruise on the surface more,instead of having to dive all the time.
If someone can give any figures or info on actual vis.range in such conditions,effectiveness of sea borne radar etc it would be appreciated.