Yeah that's the part that really gets me, especially with Dragon Trail Gardens having rain but not Seaside, and Tokyo East and Central having rain but not South. I guess we'll just never know.That doesn't make a lot of sense though. There are tracks that have rain in one layout but not in others and different time of day ranges between layouts too, surely that shouldn't need any extra data?
The time of day one is the one that really baffles me honestly to the point where I almost think it's a conscious design decision. For example in Spa you have two identical layouts (yeah the start line is different whatever) but one of them has 4 selectable times while the other layout has a full 24h. It just doesn't make sense.