Solved

Snow weather

Today I am racing in Canada. Looking at the Dark Sky page, it says "light rain with a chance of snow", but in IGP, the icon is a thunderstorm. Why is it? Is it a way to keep things in the game simple? (and btw, IGP cars can't race on snow, isn't it?)

Minimum temp in iGP is 5 degrees regardless of real life temperature.

We don't race in snow, if snow is falling in real life this is transformed into heavy rain in iGP.