@isaetoilerina You're not being a bother at all. I partly wanted the deviceconfig to see your hardware, and partly to see your settings to I could try exactly the same ones in my own game. I didn't have time to test last night as I wanted, so I was going to do it today when I got a chance.
I will say that your graphics chip is below the minimum requirement for the 64-bit version of Sims 3. That doesn't mean you can't play, but you may see strange graphics effects, perhaps including this one. Snow is particularly demanding to render, as is rain. On the other hand, this could be more widespread and totally unrelated to your hardware. I've tested rain but not snow so far, and no one else has reported it, so I really have no idea at this point.