meteograms underreport convective activity like thunderstorms
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I observe a critical issue with Windy meteograms for quite a while now, and I’ve been watching this for at least 2 years:
In unstable conditions Windy meteograms repeatedly underreport convective clouds.
Frequently the meteogram shows fair conditions, while in fact there are widespread showery rain and thunderstorms.
I believe the underreporting is due to the fact that convective clouds are not part of the direct model output.
This is a safety issue.
Fortunately this issue could be fixed easily all required input data for deriving a more realistic convective cloud forecast should be readily available.Here is a detailed example using the weather situation of the 16.05.2024:
This is the Windy ICON-D2 meteogram of Oberpfaffenhofen (EDMO), 00 Z run
As you can see, there is no precipitation forecasted.
This is what happened in the afternoon:
The meteogram does not give any hint regarding unstable atmospheric conditions.
It would be straightforward to implement this in the meteograms by using a simple algorithm using TCON, CCL (already available in the aerology – measured and forecasted soundings) and the bouyancy level BL (which can easily be calculated from the sounding data).
I suggest a visual display in the meteogram as vertical bars, which could look like so:
The vertical bars should extend from CCL to BL for the time period in which TCON is reached or exceeded.
The values derived in the abovementioned algorithm would also enable classification of the weather phenomenon, like light/heavy shower, thunderstorm, hail - even hail size.
If you are interested in implementing this improvement, I'd be happy to provide guidance.
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@wetterheidi Hi, unfortunately, this discrepancy is based on various source of forecasts and real data in our app. You can check many forecasts from different models and real time data in our radar/satellite layer. However, you can still check all of this to make your final decision.
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what @wetterheidi reported is a bona-fide bug: your app is trying to predict convective activity using the ICON* models, and reproducibly fails to do so
I consider this misprediction actually a safety issue since it fails to predict dangerous situations while it actually could - and that has happened to, and was observed by several people. To me, two days ago.
A prudent responses would have been "we will look into this and try to reproduce", "can we have more examples to figure what exactly is going on" or "how could we improve this"
to be candid @Suty : a "generic" repsonse (and that is a kind characterisation) like yours to such an issue is verging on the irresponsible - we are not talking about a typo; for instance, basing a flight decision on such a forecast is a recipe for trouble.
I wish you understood that, and you obviously dont.
To the other folk reading this thread and scratching their heads what is going on, please try the following to reproduce:
if you have a gut feeling there could be significant convective activity the same day:
- observe meteograms for ECMWF, GFS, METEOBLUE and any applicable ICON* model
- take screenshots of same
- record radar/precip/lightning activity
- then evaluate which of the meteograms actually reflected reality
You guys should take this issue serious.
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I would like to express my gratitude to the team - in particular @Filip_K - for picking up this loose end and coming up with a significant improvement of the "Rain,Thunder" layer as well as improved icons !
I reported this on our ballooning whatsapp group and there were quite a few cheers
thank you!
Michael
