It’s 2019 in an alternate steampunk/dieselpunk universe. Population growth, dwindling resources, and the evil overlords have everyone cramped into big cities, toiling away in the hope of something better. For now though, it’s enough to just complain about the weather. Smogs are a frequent occurrence, you really don’t want to breathe in the air, and to top it all off, sometimes it rains oil. The ground goes all slick, the walls have this slightly weird rainbow-y sheen, and it’s enough to make anyone think twice about heading outside if they can help it.
So: how can I get it to rain oil? I was thinking initially about strong winds/hurricanes that lift oil into the clouds, and then they fall down again, but I have no idea if that’s a reasonable suggestion. I’d like it still to rain normally, but this seemed like a way to still get oily ‘rain’. If that’s not feasible/if there’s another way, I’d be up for suggestions!
The technology level is anything industrial level or later, but no magic. Also, I’d like it be to habitable for humans if at all possible...
EDIT: Forgot to mention the kind of oil I was aiming for - probably something petroleum based, but definitely something used in a manufacturing process more than an organic or culinary kind of thing. (However, I admit I don’t know a grand deal about oil, so you’re welcome to argue the point if extra virgin olive oil is where I should be focusing my efforts).