Fritz (from Wien, Austria) told me that could be a Stereographic projection.
I tried it, implementing it in the ChartComponent project...
Obviously, that was not right...
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After watching the fax from the UK MET, the geostrophic scale explicitly says "Polar Stereographic Projection". Aha! There we are:
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Now we are talking! Polar, that's all the difference.
Now, we can even stack a GRIB on top, that really makes sense.
Kudos to Fritz!
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It's now available in the Weather Wizard.
More patterns are coming soon, keep posted.