I just attempted to get wet laps in during my practice. On the home screen it showed the weather was currently raining, I went to the setup screen, it was showing a rain icon, I ran the strategy and the symbol changed to a dry and cloudy symbol and I was given practice results that I would expect from Inters/Wets in dry conditions. This happened with both cars.
As a side note, I had my wing and ride height set to what the driver stated was ideal when I ran my dry tyre laps earlier, however both drivers are saying that my setup is way off. I'm a touch confused with it all and now don't have any wet data to go into a wet race with.