You can “customize” your weather via two .json files… I’m at work so I don’t know the exact names but it’s something like “weather effects” for defining individual effects and another “weather?” for defining the effects used in each type of weather… so it is generally easy to turn things off like rain fog etc… even the sounds iirc… the down side is that there are A Lot of things to edit depending on what you’re going for.
As far as the day/night cycle… I think @Simoyd knows something about that…