What is the value 'h' in "Levels" of the api?

[sdgfo8a7sgdf78]

This doesn't make much sense to me, surface, would be the surface I assume. But I don't know what 'h' represents, nor the value preceding it. I googled geopotential value and didn't find anything useful.

What does 1000h mean? What does 150h mean?

[vsinceac]

I guess "h" is for "hPa"; you can see the same values on Windy UI (on Levels control).

[sdgfo8a7sgdf78]

@vsinceac Thank you, it would be helpful if this was noted in the docs, or if they used the SI symbol for it

[vsinceac]

Of course adding this info in API docs should be doable and useful.
Changing the API is more difficult: it would require all API clients to change the queries, then anyway values format in queries is just a convention.