Hi , I have just been sorting out a few issues with ASA in the hi fi forum and Jim there tells me that there is nothing I can do about the following problem, as it is due to FSX. He did not elaborate why:When I use ASA to inject real weather on a high altitude airport ( In the rockys) it generates clouds ( the base layer of cumulus) which are partly submerged in the ground. The higher layer of stratus appears only a few thousand feet above ground level. If I look at the advanced weather options, I can see that the cloud layers start at 0 ft above sea level, IE FSX ( or ASA ) is not taking account of the fact that I am already at 6,000 feet above sea level. Does this happens if you use normal FSX real weather. Is it a fault in the code? IF so, this is pretty unbelievable, after all the work that has been done to make the weather and textures look as real as they do, that you cant make a simple thing like making a cloud appear at the right height above the ground happen. thx, Mark

Yes, it happens to me at high elevations when starting up the sim (say in KDEN). This said, there are some airports where the cloud layer can be correctly below you in the valley (from Courchevel France for example where clouds can very well be in the valley yet the airport is above the first cloud layer). I can't say I frequently have large cumulus clouds that show up 10' AGL with ASA and I think you're right in terms that weather programs may not take into account current ground level altitude to correctly render layers that are near or below current altitude. It's odd to have a thunderhead at nose level.To do this perfectly would probably require the weather program to have topographic data and the ability to place each cloud based on terrain elevation. I'm not aware of any API that allow for this easily as FSX thinks of those things as layers and cloud type, not XYZ position and current elevation - that's left to the rendering engine to do the necessary occlusions. I'm with Jim that there's a big limitation there with FSX, however, clouds do work in most cases and products like ASA do fix a lot of what can be fixed. Probably merits a review as the depths of the APIs and hacks come forward, but not the easiest thing to do in my view. The odds to get a better API to gain access to this are not good as we know.Cheers,E.

To do this perfectly would probably require the weather program to have topographic data and the ability to place each cloud based on terrain elevation.

Actually if you read weather from SimConnect at an airport location, you will get the ground altitude as part of the return. And the ground altitude under the aircraft can be easily obtained as a SimConnect variable. I think weather programs should always endeavour to produce clouds AGL -- after all the METAR reports they use pride AGL cloudbases, not AMSL. I think you'll find ASV6.5 used on FSX doesn't suffer this problem, and that uses FSUIPC (which in turn uses SimConnect on FSX). The one real cloud related thing programs CAN control reliably through Simconnect is the cloudbase -- SimConnect provides no thickness settings and even the type and coverage is precarious (not directly deterministic).I had cumulus clouds on the tarmac at Madrid this last weekend. There's really no excuse there. It's at about 2000', but so is most of the land around it for a long way -- the exception being the mountains to the north which are a lot higher of course, not lower.I never noticed such a problem with ASX not ASV6.5 before it. I have just updated my ASA installation with the SP released this week -- I do hope that improves matters.RegardsPete

Open the FSX weather settings dialog, do not change anything and click OK.FSX will correct the cloudbases most of the time.Alex

Yes, it happens to me at high elevations when starting up the sim (say in KDEN). This said, there are some airports where the cloud layer can be correctly below you in the valley (from Courchevel France for example where clouds can very well be in the valley yet the airport is above the first cloud layer). I can't say I frequently have large cumulus clouds that show up 10' AGL with ASA and I think you're right in terms that weather programs may not take into account current ground level altitude to correctly render layers that are near or below current altitude. It's odd to have a thunderhead at nose level.To do this perfectly would probably require the weather program to have topographic data and the ability to place each cloud based on terrain elevation. I'm not aware of any API that allow for this easily as FSX thinks of those things as layers and cloud type, not XYZ position and current elevation - that's left to the rendering engine to do the necessary occlusions. I'm with Jim that there's a big limitation there with FSX, however, clouds do work in most cases and products like ASA do fix a lot of what can be fixed. Probably merits a review as the depths of the APIs and hacks come forward, but not the easiest thing to do in my view. The odds to get a better API to gain access to this are not good as we know.Cheers,E.

Hi E, some of what you said went over my head, but surely it does not need to be so complex. If you are taking off from an airport that is at 6000ft above sea level, all FSX has to do add the cloudbase figure to the airport height above sea level. You dont need every cloud and mountain to be calculated. ( have I got this right, cloudbase is measured from ground level at whatever point you are, not sea level ? ) What it seemed to be doing in my scenario was depicting the cloud base starting at 0ft above sea level. The cloud layer was 7000ft thick, and just the tops were sticking up through the ground. What clouds ever start at 0ft above sea level ? What it probably meant was that up in the mountains, the cloud base was 0ft above ground level. So how does FSX work out where to render the clouds. And up to what point to programmes like ASA control this? thx, Mark

have I got this right, cloudbase is measured from ground level at whatever point you are, not sea level ?

Well, nearly right. The measure is from the point at which the clouds are observed -- i.e. the weather station, which will usually be somewhere near an airport.

What it seemed to be doing in my scenario was depicting the cloud base starting at 0ft above sea level.

I'm wondering if this is related to the facility in ASA to drive the weather "directly" using Global settings. Try turning off Direct Wind Control and Direct Visibility Control, if you have them enabled.With Global weather mode in FSX, all cloudbase data is supplied AMSL -- it has to be because being "global" there's no other base for it to choose. What ASA should be doing is adding the nearest weather station's altitude to the cloudbase figure before submitting the METAR string data to FSX.The more I think about it the more I am sure this must be the reason for the problem. I only just recently switched to trying DWC, and last weekend was the first time I saw clouds on or below grounsd. Hmm.Anyone reporting this on the HiFi forum? Anyone still getting the ptroblem with the latest Service update for ASA?RegardsPete

Open the FSX weather settings dialog, do not change anything and click OK.FSX will correct the cloudbases most of the time.Alex

So, before you hit fly now or after, when you are in the cockpit ? Because ASA injects weather after you start up. And do you have to go right into the advanced screen, where the cloud layers etc are shown? thx, Mark

Well, nearly right. The measure is from the point at which the clouds are observed -- i.e. the weather station, which will usually be somewhere near an airport.I'm wondering if this is related to the facility in ASA to drive the weather "directly" using Global settings. Try turning off Direct Wind Control and Direct Visibility Control, if you have them enabled.With Global weather mode in FSX, all cloudbase data is supplied AMSL -- it has to be because being "global" there's no other base for it to choose. What ASA should be doing is adding the nearest weather station's altitude to the cloudbase figure before submitting the METAR string data to FSX.The more I think about it the more I am sure this must be the reason for the problem. I only just recently switched to trying DWC, and last weekend was the first time I saw clouds on or below grounsd. Hmm.Anyone reporting this on the HiFi forum? Anyone still getting the ptroblem with the latest Service update for ASA?RegardsPete

Hi Pete, funnily enough, I do have those settings enabled as well. I will try disabling. Thanks for the help!!

So, before you hit fly now or after, when you are in the cockpit ? Because ASA injects weather after you start up. And do you have to go right into the advanced screen, where the cloud layers etc are shown? thx, Mark

After fly now and after ASX / ASA is done updating the weather.Sometimes this has side effects like fog appearing, if nearby stations report it, etc.Alex

These low level cloud layers happen without external weather generation, infrequently, yet they do happen. I wanted to say this is primarily with what I call the "cotton balls", the sparse clouds you get with default weather, and weather generators not running (so no ASA or REX running). The solid layers have less of an issue (this is just my perception, not a scientific fact). I just got done with a virtual visit to PNG with fairly high ranges and deep valleys, and I had a cumulus right on the edge of the runway without ASA running. Not impossible, but odd. I can't say I had the problem on relatively flat ground, so the note above with the problem at 2,000' I've not noticed - I've seen bad weather with fog and low level clouds - that seemed a reasonable rendering of terrible flying conditions :) Perhaps it's just that the incorrect type of cloud is rendered. Again, still not convinced this is an ASA specific issue.E.