Searched for something like this and the site stated to make sure Ambient Occlusion was on.  Well, mine was already on and the rain was falling through the base, regardless of the roof material.  Any ideas how to fix this?

Its one of the main reasons that FP disabled the rain several years ago, they got tired of the complaints about this very thing, There is as far as i know no way to fix it or FP would have reintroduced the rain again, there was also the problem of it raining in the snow biomes instead of snowing,

Take it up with Unity, it happens in every Unity game.

I didn't think there was a logical solution.  Thought maybe someone found a work-around.  Thanks, guys!