Are cloud bases in new METAR system in AGL or MSL?

Seems a fellow user has found a possible solution to this bug. Updating the posting accordingly:

So before I log this as a bug, can anyone else seem to confirm that cloud bases in the new METAR injection system are being rendered at the MSL altitude rather than AGL altitude? I’m well aware that in real life, cloud bases in METARs are strictly AGL. Rather, it would seem after a few tests, that in the sim they are all being rendered as MSL altitudes.

For example, at Reno this morning the METAR read OVC050. However, the clouds were at the surface, which just happens to be at 5000’ MSL. The clouds should’ve been at 5000’AGL or 10,000’ MSL.

This would also seem to indicate a possible reason that the sky conditions last night at Lugano in the sim appeared to be clear skies, yet the METAR appeared to show a low overcast layer. With an altitude of 915’ MSL, perhaps a METAR showing OVC008 would just not appear if they’re using MSL altitudes as it would be underground.

Can anyone else confirm?

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I was wondering about this myself. Good observation. I’ll make a note to check on my next flight.

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Good thinking! I’ve moved your topic to Bugs & Issues, so it can be found and voted on :slight_smile:

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I’ve been testing this some more, and it does seem to be the issue that plagues us right now.

Just a quick note for testing this…. It is easier to test when the reported cloud bases are at least a few thousand feet above ground level. This is because their datum point on cloud bases is most likely not at the true base, to give the clouds some variety.

The error is most noticeable in the thousands of feet range versus the hundreds of feet range.

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I can confirm this bug! The clouds from the METARs are rendered at MSL. METAR report the height of clouds AGL not MSL!

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Current observations at KAGC - Allegheny County Airport near Pittsburgh:

Current METAR: KAGC 191553Z 10SM OVC037 01/M06 A3045 RMK AO2 SLP327 T00061056

Clouds are broken and at 3600 MSL on average with the bottoms being around 2500-2700 ft MSL. The elevation at AGC is 1252 ft, so the base should be closer to 4500-5000 MSL.

Interesting though that the METAR is not reporting any winds but the sim does have winds from 285 at 9 kts, so things are definitely blended somehow.

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Yeah the winds there are just missing from the METAR. So, winds must be interpolated from n]other nearby METARS. But thanks for the report. It does seem to confirm the sim renders at MSL, rather than AGL. 3700-1200 = 2500. So, does seem to be the issue. Thanks for the confirmation report!

Cheers,
Rob

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Same issue here.

METAR at EGLL this morning (elevation 83 feet’) included 10km+ vis and OVC/015.

The conditions appeared to be as if I had BR 2000 and BKN/002. I agree there is a strong likelihood that there is a mixup with AMSL and AGL. Generally clouds are depicted way too low.

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How thick were the clouds by chance? I think they are using some sort of reference line for cloud bases, that are not at the true base of clouds, for reasons of variety. If the clouds were very thick, it is possible that the true bases were down lower than the base reference. Such as in this picture.

But, this is just speculation.

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I didn’t record tops but I would guess they would have been around 3000-4000’.

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Aha, that’s why I see clouds half way into the ground. Good catch > I guess a hotfix tomorrow.

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Was wondering why everything has been shrouded in low level pockets of fog.

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Good find! If this is true it would unfortunately mean that Asobo has no clue what they are doing :sweat_smile:… I’m getting flashbacks to the wrong temperature error implementation a few updates ago…

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Also raises the question, how did they implement wind? Wind direction from METAR and TAF are referenced to true north, tower and ATIS winds are magnetic, might also be a problem area. Did they implement magnetic variation correctly?

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It really looks like the cloud base is way off. Before SU7 the sim Live Weather @ LKPR was usually spot on.

Some real time testing:

Sim Live Weather @ LKPR (elevation 1234’):



Real Weather @ LKPR:



image

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Yeah, the clouds are absolutely off. Started to suspect something was off when every single rendition I saw was clouds hugging or being half-way in the ground.

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Please mods mark this one up as “Bug logged” It’s very clearly a bug and needs fixing asap. We cant be waiting a month or more to get this sorted, it needs a hotfix and quickly!

How on earth this got through “testing” is beyond me.

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Good observation, I hope this bug reports is picked up before the next update in 2022 as this is quite sim breaking. I.e. what could have been a mvfr day is now not possible

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Would be crazy if they kept it like this into 2022, this makes weather reports and the entire foundation of flying according to weather completely useless. Pretty much the foundation of sim flying.

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The SU7 weather depiction is really bad. Two examples :

Imgur

Imgur

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