Thank you OverRated! The rain ‘should’ only spawn splashes on collisions as OverRated said, but I have noticed as well that sometimes it is not always as accurate as I would like. I think this has something to do with the way Cascade reads collisions.
As for the rain, if OverRated’s suggestion does not work, I would recommend using the fog sphere to fill in the distant rain instead of the old cylinder I used to use. This is what I am doing in my own projects here at work and with some value tweaking it works quite nicely.