[S] Weather Effects Occurring Inside Structures

I don't think it is that. It's not weather that's the actual issue, its designation of inside vs outside that's broken. The weather indoors is more a symptom of the issue. 
Probably more to do with the new pack that had to be fitted in and where they made the change that allows for /home/business/employees only / on the same lot.  The changed how home lots work essentially.  Now everything is seen as 'outside' in the game, making it easier for other sims to visit your lot as if it's a retail lot ( normally outside/not on home lot). Because sims inside can now also do the 'watch stars' interaction. It's therefore not an issue with seasons, but there not being an 'inside' in the game anymore. On home lots and community lots.  They broke the game for the new pack. And changing it so it works at intended might break the new pack in return. Which might be why they are ignoring the issue. Fixing it will break other things, and while trying to sell people the newest pack that's not a good idea for them. 
Might also have broken the 'Stay Over'  function, now sims that are visiting can't sleep as you can't assign them a bed. Also has to do with 'home lot' functionality.