The state of the XP 12.00 RTM weather engine

[Bob Scott 7,722]

This thread is not being started to provide unhappy campers a venue to b*tch...if you feel the need to vent and rant at LR over this, do it elsewhere.  I'm looking for a factual discussion about weather depiction here...park the sarcastic invective and/or glowing testimonials about other aspects of the sim at the door, please. 

What I want to talk about is what's actually going on (or not going on) in XP12's weather subsystem in the 12.00 release version.  I think it's important that people considering XP12 know what they're in for now that this is branded a release (final, in LR's own words?) version and no longer a beta.

Yes, there's an XP12 demo version...but its limited scope (in both time and location) doesn't really allow one to experience the deficiencies in winds aloft or a wide variety of weather depictions not local to the coastal US Northwest.

As a mostly-satisfied XP11 (plus ASXP) user for the last nine months, what I found in the state of XP12's weather engine at release was quite unexpected--better looking but practically random weather conditions.

The "real" weather engine is really quite operationally dysfunctional and unpredictable.  Last night, for example, we had been in a driving snowstorm for over four hours here locally, and when I started the sim here, it was raining and +8C.  In general, in dozens of scenarios I tried, "real" weather in the sim differed dramatically from what was either observable outside or reported on real-world METAR.

I've seen a few statements opining that the extent of the weather problems are just that the weather is as much as 15 minutes off of real-world--that, again, has not been my experience at all, nor has it been for a wide cross-section of users reporting big problems on other XP-specific forums.  The most basic and measurable weather parameters--temp, QNH, winds--often deviate from real-world weather significantly, and cannot be explained away as owing to a 15 minute time delta.  Downplaying the real magnitude of the problem by dismissing it as just a few minutes of lag is neither helpful nor accurate.

Winds aloft don't often resemble real-world based on what's on a Simbrief computer flight plan nor by a manual inspection of the winds in the decoded current grib file, varying widely in both direction and speed, making fuel planning for longer flights difficult to impossible.

The neat accumulating snow effects depicted in at least one pre-release video have not been repeatable for me, as so far I haven't gotten anything but rain even when sitting in the middle of a raging snowstorm.

I truly don't see how one can effectively include forecast or currently-reported weather in the planning and execution of a flight on this platform, except perhaps by manually setting one-over-the-world weather.

In short, for potential users that consider weather an essential element of simulated flight, this may well prove a major, show-stopping deficiency in the XP12 sim platform, as released and currently available. 

 

[MrBitstFlyer 3,882]

It has been announced,  on this and other forums, LR is working on a big weather update. I don't think for one minute the weather will be perfect after it, but I personally wouldn't expect it to be so.  Experience of all the major sims over the years have demonstrated these things are in constant development.  

For a 'first' release of the sim, I feel we have a good weather base.  I personally would prefer not to wait another year for XP12's release for perfect weather, but rather use the great start we have and go through its development.  Realistically, LR needs to compromise between development and releasing for financial reasons, and I feel they got it right.

In the meantime, I don't see why anybody couldn't set the weather manually, if they need to fly in weather exactly as it is out the window.

Edited December 29, 2022 by MrBitstFlyer

[peroni 541]

1 hour ago, MrBitstFlyer said:

It has been announced,  on this and other forums,

Is there an official announcement you could link to, please? 

[MrBitstFlyer 3,882]

17 minutes ago, peroni said:

Is there an official announcement you could link to, please? 

People involved with LR have said in various posts there is a big weather update on the way.

[coastaldriver 920]

Bob - I do not know where XP12 actually sources there weather data (NOAA? WMO?) I can pull up the the real world Aerodrome and other Forecasts via the local BOM - Aviation Services for any area I choose (In other words I have online access to all world aviation forecasts, met reports and route forecasts etc.

So I used a small place called YARM - Armidale in NSW Australia. The actual weather there at the check was SCT 009 and BKN 016 Easterly 12 kts Vis greater than 9999. The forecast also provided was for that but BKN 020 changing to RASH from 0000 hours.and SCT at 020. There was also a prob of FOG indicated for a short period when I started the sim. This is a good mix of both forecast and actual weather for the same place.

The sim was showing SCT at or near Ground level but clear at the field and basically SCT but not BKN at about 4000-5000 above the field. I reset and reloaded the weather again via the main menu at the main menu the weather was as presented in sim but this still did not match the Real World Weather - Actual or Forecast which I also had in front of me. It had the location correct. 

So I have no idea where it is getting that weather from. The Forecast would have been valid several hours previously and the metar of course is to the half hour correct. 

It is nice you can check via the setup parameters what the weather actually is but you cannot access this insim or flying which is a pain as there is no means to determine either what is forecast and what is actual.

Definitely out of whack. I have yet to do a long range run where high level forecasts only are used. 

Postscript - The issue of weather level and aerodrome elevation is now also critical. A TAF or METAR will report cloud above the aerodrome reference point or in other words the height above the ground at the airport. Forecasts reference cloud levels to height above mean sea level or in the case of high level forecasts with reference to various pressure levels in the atmosphere. This is critical to any weather engine displaying correct weather. 

Why do I mention this? In my test case described above it was clear that the cloud being presented (was reasonably accurate to amount) but the cloud height was being shown as if the airport was at sea level so an area forecast level in which case it was reasonably accurate for height except YARM is 2500 ft above sea level so the cloud was being shown in that manner not relevant to the local altitude. 

 

Edited December 29, 2022 by coastaldriver
Additional Information

[mSparks 2,088]

Ive seen two sources (at this moment only two) of sim instability/crashing (excluding 3PD stuff)

one is flying with download real weather enabled during flight. for now Ive been using it to grab some weather then going back to manual. reasonably sure of this. 

The second is having chrome open - really not sure about this, it could have been the weather download.

new weather system is far from perfected yet, but also a huge - gigantic - improvement over XP11 even with its weather add ons - especially if you are staying below the clouds - above the clouds needs a lot more work, visually and functionality.

last I heard, main LR dev commitment there at the moment is getting the sdk stuff together so 3PDs can suitably abuse it. 

Edited December 29, 2022 by mSparks

[coastaldriver 920]

The weather depicted is more than reasonable - cloud, precipitation and weather phenomena- in a variety of places. But as I suspected it is not matching the real world weather correctly.  I can only speculate but I am hopeful that HIFI will come up with an XP12 version of AS soon as they have the SDK - because their inflight menu options are vastly superior to the clunky interface that XP12 has and they have the synthesis between metar and forecast done well. 

I cannot say if the full range of precipitation (snow and ice as well) is being shown! Northern Latitude users may have more idea. 

[UrgentSiesta 936]

In terms of the improvements over v11, I have to say i'm fairly satisfied - for now - given the x.00 release version, esp combined with all the other fundamental improvements/rewrites, etc. So satisfied, in fact, that i'm not in the least tempted to go back to v11 (which, in my case, would require a re-install).

It may also help to consider, from the horse's mouth, what LR have done in v12 "atmospherics" (visual as well as effects), and what their Vision is:

https://developer.x-plane.com/article/x-plane-12-flight-model-report/#Real_Weather

When you read that, and listen to other interviews/presos (Deep Dive, etc.), it seems clear to me that Weather is far from complete, and it's inconceivable that LR believes it is, either.

I think of P3D, still with no sign of live weather at all, the long and continuing journey of MSFS' atmospherics simulation, and even DCS World's recent improvements that are visually impressive, but remain grossly simplistic.

And relatively speaking, I still say, "Not bad, Laminar. Not bad at all."

Whether v12.00 is "ready for Prime Time" is entirely a subjective matter, and the "ready" threshold will vary greatly across the user base.

[GoranM 3,772]

9 hours ago, Bob Scott said:

I'm looking for a factual discussion about weather depiction here

Those of us who know, are more than happy to provide the facts.

9 hours ago, Bob Scott said:

What I want to talk about is what's actually going on (or not going on) in XP12's weather subsystem in the 12.00 release version.

In my area (close to Bankstown Airport), the weather is spot on.  Obvioously, I can't go looking at all the airports around the world to double check how accurate the weather is, so I'll take your word for it.

9 hours ago, Bob Scott said:

I think it's important that people considering XP12 know what they're in for now that this is branded a release (final, in LR's own words?) version and no longer a beta.

Indeed, X-Plane 12.00 is considered final, just as LR announced.  They did use the version number 12.00 in their announcement.  The list of issues that were slated for fixing for 12.00 were addressed and taken care of.  Putting the focus on the weather, this was too big of a job to fully address for 12.00, and is scheduled for a future version of XP12.  It could be 12.01, .02, etc..., but for now, none of us know, because those incremental versions could be beta's.  I'll use a hypothetical and assume the next stable version of XP12 will be 12.10.  And it's very likely weather will be sorted out for that version.  LR have announced what plans they have for the weather in the dev slack group, but that group is under NDA, and unless they tell us we can share something, none of us in there can mention what the weather information is.

Regarding the incremental versions of XP12, this isn't something LR or any of us who use X-Plane are using to "cheat" or as a cop out (as I've seen mentioned in other forums).  These version increments have been used since the very first version of X-Plane.  

9 hours ago, Bob Scott said:

As a mostly-satisfied XP11 (plus ASXP) user for the last nine months, what I found in the state of XP12's weather engine at release was quite unexpected--better looking but practically random weather conditions.

The weather, as I said, is getting improvements, as well as an open API (I think).  Developers asked for it.  LR were aware of the issues in the weather being out of sync in one of the earlier beta's, and Ben Supnik announced big plans on fixing it. It may have had a partial fix (my areas were fixed), but obviously, it's apparent the syncing issue isn't fully fixed.

9 hours ago, Bob Scott said:

The neat accumulating snow effects depicted in at least one pre-release video have not been repeatable for me, as so far I haven't gotten anything but rain even when sitting in the middle of a raging snowstorm.

Ice and snow accumulation is definitely modelled.  That was taken just now, on my PC, in the latest public XP12.00 release.

 

 

Edited December 30, 2022 by GoranM

[bogdansrb 230]

I really hope Laminar won't consider the current state of the weather "good enough", and I'm not talking about fixing the known bugs. I don't like that the clouds are too blurry especially those in close proximity, I haven't seen any convincing cumulus clouds, snow depiction is poor and there is no snowfall, and sometimes rain comes out of nowhere. I would also love to see storm "curtains" and better defined storm areas, and I hope that weather radars would be implemented soon (I assume developers are waiting the API). 

Hopefully we won't need something like ASXP to fix these.

[GoranM 3,772]

20 minutes ago, Paul Deluca said:

Many thanks Goran.  Good to see you back here.

Yeah, Ben just got back to me.  Like mSparks said, official word is some time next year.  

3 minutes ago, bogdansrb said:

I don't like that the clouds are too blurry especially those in close proximity

Volumetric clouds tax hardware.  A lot.  I'm not in a position to comment on the intricacies of coding weather and clouds, but the more detail you add, the more your hardware will take a hit.  A compromise has to be found somewhere.  And that compromise comes through testing.  Have you tried increasing cloud detail in your settings?

5 minutes ago, bogdansrb said:

snow depiction is poor and there is no snowfall

Snowfall is coming.  Not sure what you mean by snow depiction is poor.  I posted a screenshot of snow on the ground a few posts up, and ice on the runway.  Can you be more specific?

6 minutes ago, bogdansrb said:

and sometimes rain comes out of nowhere

Can you be more specific here, also?  My office looks out to my front yard, and often times, I would see a rain bomb just hit, and I would say, "Where did THIS come from??"

8 minutes ago, bogdansrb said:

I hope that weather radars would be implemented soon (I assume developers are waiting the API). 

We're waiting for this for the CL650.  It's been confirmed that it's coming.

 

[GoranM 3,772]

26 minutes ago, Paul Deluca said:

Good to see you back here.

Thanks.  A break is sometimes needed.

[mSparks 2,088]

3 minutes ago, GoranM said:

 A lot.  I'm not in a position to comment on the intricacies of coding weather and clouds

I spent a fair bit of time on

https://github.com/mSparks43/Volumetric-Clouds

and then

https://github.com/mSparks43/Enhanced-Cloudscapes-Engine

So I feel pretty safe saying what LR pulled together already for XP12.00 weather is a massive accomplishment, far beyond anything I expected. 

That's not to say what is left to do isn't just as hard, we're in wild west country, none of this has been done before. But its worth mentioning I think that historically what they are trying to achieve was typically done by

https://www.zdnet.com/article/this-billion-dollar-supercomputer-will-be-used-to-create-super-accurate-weather-forecasts/

And they are not even close to putting a highly detailed 747 simulation through it at 98fps.

[bogdansrb 230]

Quote

Volumetric clouds tax hardware.  A lot.  I'm not in a position to comment on the intricacies of coding weather and clouds, but the more detail you add, the more your hardware will take a hit.  A compromise has to be found somewhere.  And that compromise comes through testing.  Have you tried increasing cloud detail in your settings?

Cloud detail is set to maximum. And I think that for the maximum setting they can look better. I know it's taxing on the hardware but that can be adjusted to preference, that's why the slider is there. As a comparison, clouds in MSFS have much better definition without affecting performance that much (in fact I get better performance there).

Quote

Not sure what you mean by snow depiction is poor. 

Every area that is covered with snow this time of year shows only patches of snow in the sim, if at all. I read that x-plane shows snow on the ground only if it's snowing at that moment, not overall snow coverage.

[bogdansrb 230]

Quote

Can you be more specific here, also?  My office looks out to my front yard, and often times, I would see a rain bomb just hit, and I would say, "Where did THIS come from??"

I don't really know how to explain this better. You're flying and it suddenly starts raining, sometimes even if clouds are further away from the plane. I've also seen that it almost always rains inside the clouds even if it doesn't on the ground.