Saved weather (WPR) files

Has anybody figured out the behavior of the simulator GUI for custom weather? In general, I think that weather is loaded correctly, but the GUI doesn’t display it correctly, and if you save from the GUI, it will screw up the weather. (Which you can sort of tell by looking at the .WPR XML files that are saved.)

Here are some things I’ve seen:
#1: If Gust information is in the weather file, it is loaded. If you make other weather changes unrelated to gusts, it is retained when you save the .WPR file in the sim. However, if you change anything about a gust, it is no longer saved when you save the weather.
#2: The ground layer is “special”, where “special” might mean “buggy”. In that layer, the wind speeds are displayed in the sim as half the value in the .WPR file. For example, if I have a WindLayerSpeed of 15 knots, the sim displays it as 7.5 knots. I believe if you modify the wind in the GUI, the values from the GUI are doubled when written to the file. No other wind layers seem to have this behavior.
#3: When wind and gust info is saved, most fields are saved with the values that were loaded. Exceptions: GustWaveDuration is always set to zero. GustAngle is changed to a different value that appears to be (a*0.94384333 + a), where ‘a’ is the original GustAngle. For example, 10 degrees becomes 19.438 degrees, and 300 degrees becomes 583.153 degrees.
#4: The wind gust speed slider and display show zero until you click to a different wind layer and back again.

I think my best bet is to just edit the XML directly, but I’m curious if anybody else has sorted this out.

The Weather Preset UI gets worse every time they say they are going to fix something in it. I’ve given up on them ever fixing a pretty fundemental part of any flight sim.

I edit my .WPR files by hand and then load them in. As long as you don’t touch any sliders it appears to honour the vales you’ve added in the XML.

An aside, they added a boundary layer “feature” that halves the wind speed at the surface. It is supposed to simulate the drag/slow down you get from the gradient wind. It doesn’t appear to have been done very well.

Useful but incomplete docs on .WPR are here: Weather Definitions

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Here’s a helpful discussion I found about the ground layer issues:

I’m not sure but I think that one got fixed.

I meant that it explains why the ground layer is halved in the GUI. My observations were from SU8, by the way.
I don’t think it addresses #1, #3, or #4.
I agree with that other thread that the approach they take with the geostrophic wind in the GUI isn’t a particularly useful approach.