I did not manage to get it to rain. What I tried:
- world#setStorm(true)
- world#setStorm(true) + setting weatherDuration after
- world#setStorm(true) + setting weatherDuration before
- world#setStorm(true) + setting weather duration before and after
I get nothing. Debug messages show that world#isStorm is true but if I check it a tick after it is false again. Also setting storm changes the weather duration with no noticeable pattern.
However world#setStorm(false) did work just fine.