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Advanced weather doubts.

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Advanced weather doubts.

Postby Aomurasaki » Sat Sep 19, 2020 7:13 pm

Hello, i have tried the advanced weather entering a METAR string by myself and i had some doubts. e.g. when i click the Apply button the weather changesImage https://ibb.co/9yMVZnXbut when i pressed OK weather changes again Image https://ibb.co/wdbS0QdAnyway i assumed that i have to click on of them according to Wiki:Weather:Quirks and Caveats:Step 4.
Also when i set +TS there's no visible lightning surrounding, there's a lack of clouds? or what am i settiing wrong? Imagehttps://ibb.co/9yMVZnX I also entered the string in the qtlauncher Imagehttps://ibb.co/0fbbp35 but after press apply or ok in the dialog, there was not thunderstorm surrounding.
Finally i have set the thunderstorm preset scenery and the thunderstorm appears, then i entered again a manual string but just changing some aspects: MMTG instead XXXX ICAO,day, TS aloneImagehttps://ibb.co/zFvCdMQ and i just say wtf its rain lacking ? added RA and just rain appears Imagehttps://ibb.co/KyCMjG9
I'm not understanding what is happening, can somebody help me. Any suggestion is welcome.
EDIT: I finally got some lightnings with this setup(sorry here was a wrong picture) i'll keep trying different configs.
Aomurasaki
 
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Callsign: LIGHTHWK01
Version: 2020.1.1
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Re: Advanced weather doubts.

Postby Thorsten » Sun Sep 20, 2020 6:17 am

As for the first issue, there's an infinity of cloud configurations that can be described by a single METAR string, so every time you click OK or APPLY you'll see one of them generated.

Then, AW is a physics based weather engine, so when you enter a METAR string there's a two step parsing process. First, the FG METAR parser dissects the string you have entered and stores the parsed results in a series of internal properties. That parser doesn't recognize all syntax elements that in principle are valid, I remember that it simply ignores some forms of entering a thunderstorm.

Then when you use AW, the AW parser tries to make sense of what you enter and selectively ignores what it can't do/ considers unphysical (conceivably you could enter a METAR string that specifies heavy rain but no clouds and 50 km visibility - almost certainly AW will not follow your request).

Since a thunderstorm is a rather complicated beast that affects clouds and wind patterns all over the place, when the parser decides to recognize the input as thunderstorm, it will basically ignore everything else in terms of clouds and render a dedicated thunderstorm tile. The storm will be 'somewhere' in the vicinity, but there's no guarantee that it's right over you.

The upshot - AW is designed to reproduce the physics of weather patterns, the METAR-mode is a user-requested grafted add-on that tries to map you close, but if you for some reason require the exact weather pattern of your string, do not use AW, it doesn't do that by design, and it really works much better in offline weather mode.
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Re: Advanced weather doubts.

Postby Aomurasaki » Sun Sep 20, 2020 7:14 am

Thanks.
I'm really impressed with AW.
Now I feel more comfortable using METAR-mode, I am not a meteorologist but I have had physics courses and I think I can have an acceptable understanding of how the local climate should work, I did try various configurations and read several documents including your article "The art of cloud and weather rendering ". I made a quickly ss https://ibb.co/YcPYxtK
On the other hand i was expecting this fact
Thorsten wrote in Sun Sep 20, 2020 6:17 am:That parser doesn't recognize all syntax elements that in principle are valid
when i see the large ammount of info items in the real METAR strings(I am aware that this is not necessarily the reason). In particular i find out about the existence of fractus clouds, and their abbreviation CUFR or STFR and that didn't work XD.
I'll continue documenting myself. Regards.
EDIT: has someone ever generated funnel clouds or a tornado?
Aomurasaki
 
Posts: 30
Joined: Mon Jul 13, 2020 11:38 pm
Callsign: LIGHTHWK01
Version: 2020.1.1
OS: Linux


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