What about, 'If I'm going to be treated like that, I'll leave!'
be going to is used to talk about future actions that have some present reality.
Yes, your sentence have some present reality. You can predict the possibility of a future turmoil ("churning clouds").
I was thinking merely about the "volitional" aspect of "going to".
Theoretical approach to a language has its cons sometimes. I cannot have practical approach you know (I am a NNES).