Saw the trailer and to be honest, I find the whole inclusion of weather/effects to be unnecessary especially since weather have no affect on a car performance other than tire traction.
Now if this were a flight sim like game Aero Elite Combat Academy, Falcon 4.0 or Microsoft Flight Simulator I could understand the inclusion of weather effects(as those games already use varying weather systems) since it actually affects a aircrafts performace may it be landing, taking-off, aerial combat(severe weather can blind a missile from hitting its intended target), etc, however since this has to do with cars the inclsuion of weather effect was just unnecessary.
In the end all this trailer tells me is what PD was wasting time adding a pointless feature for no reason.