Hmmmmm -- I could be wrong but it seems to me you need to specify some "obstruction to visibility", like fog, rain, snow or cloud before LOW VISIBILITY can exist.

This is a silly anology, I know, but what you're doing is like firing a gun without first putting a bullet into it.

Cal

This is the same thing. You must HAVE a ceiling before you can lower it and, by METAR definition, a "ceiling" exists only if there is 5/8 of the sky covered by cloud.  In other words, you have to input clouds. His original post says it remained SUNNY even with minimum visibility.  Therefore, it is reasonable to conclude there was no rain, snow, fog, sleet, blowing dust, smoke or haze set into FS's advanced weather panel to constitute obstruction to visibility.

Like I said, you gotta load the gun before firing it.

Cal

I have the same problem, I think I know what ur talking about.  (not sure if anyone else does though lol)

Does it look something like this?

This picture was taken with overcast skies and 2 mi visibility on the default ceiling. (whatever it's set to when you turn it on)  Note that all the scenery is perfectly clear, like it would be on a clear day, untill it suddnely dissapears into a thick skyblue "fog" that looks like a wall  

In my case fog works in some games and not in others, so I think my video card just isn't compatible with some things.  (But I'm not too hardware literate, so I could be wrong.)