Why does fog disappear?

[intothewind]

Hello!

I don't usually fly when under IFR, but some time ago I decided to see what the fog and clouds would look like from above in FS2004. To my surprise the fog vanished entirely. This only seems to happen when I go above it. I have to be below it for the fog to come back.

Perhaps someone has had this happened to them before, or knows a fix. If so I would appreciate any help at all.

I don't really care much because I do not fly when airports are IFR, but I still would like to be able to have fog behave normally, IF this is abnormal behavior in FS9.

Thanks!

[jimslost]

Just for grins, can you specify how you setup your foggy weather? I tried using the custom weather option to create a fog layer from 200 to 1500 feet, but I hadn't broken out on top when I finally leveled off at 3000. When I selected "Fogged In" from the basic weather window, I ended up with patchy fog that more or less acted as you describe - when descending, I could see the runway until suddenly I was IMC.

You know you're probably going around when you descend into the fog bank just as your copilot calls, "Two hundred to minimums."

[intothewind]

Thanks jimslost

I discovered this while entering an airport that was under VFR. After I flew for about a mile or so straight out, I noticed there was fog all around all the sudden. This is weird also. I don't know if the Simulator is just not capable of simulating fog showing up and leaving like it does in real life. For me it just appears all the sudden. Although I have notice realistic fog at the dawn. First is gloomy and foggy and then slowly the weather begins to clear. But I didn't check from above to see what was going on that time.

I tried the fogged in option, it was the same result, of course the fog was already there when I enter the airport.

I don't even see patchy fog like you said, there is just nothing. I did forget to say, the cloud do stay, they do remain there, is just the fog that is gone.

[jimslost]

Wish there was a detailed explanation on how some of this stuff is supposed to work. Then we could compare it to the results we see and maybe determine whether the "abnormalities" were the result of operator error or a lack of understanding of program/system capabilities. In my case, I vote for the latter explanation.

[intothewind]

Well jimslost

I really don't know much about it technically speaking, as an anything that you could move around inside the FS9 folder that would change anything and stuff like that.

I made sure everything was on high: View Distance, 3D Clouds etc... but that fog still is not there after I go above it. Maybe it really is just on of the limits FS9 has. I wonder if FSX also has this problem or if fog is realistically rendered.

I do forget tho, you said you do see patchy fog. I have an Nvidia system and pretty much everything works great. If you also have Nvidia, which is the only thing I can think of that would make a difference, then it may just be a limit of the Sim.

Thanks for the replies.

[windrunner]

As I remember, Fog is a cloud layer in the FS environment and it is added following the different metars on your way. The way you see the "fog" depends on the clouds textures you have installed. Some are good and looks like fog, others will look like simple stratus over the terrain.

For those who want a more realistic experience with real weather, I advice you to install a module called FSUIPC (there is free and a payware version). The free version can be downloaded at any site, and it will fix some of the most gruesome errors when reading metars and "installing" the data into FS9, not just clouds and fog, but also winds, the speed of weather changes, and many others parameters.

One last thing: remember there is a bug in the way fog and clouds layers are managed in FS9, because the world data is usually translated in feets. It does works for those who fly in USA but it doesn't for the rest of the world and its excentric Metric system. The only way to solve this is to install a modded "Weather.dll" able to read the fog layer in meters and not feets.