Polyphony Studios is the studio behind the highly anticipated Gran Turismo 5. Many gamers have been questioning if there will be day/night cycles and weather changes within the game itself. Well recently when a french website, JVN.com, visited Polyphony studios those questions and more were answered.
Not only were the day/night cycles confirmed, but rain inclusion was as well. Some other features were discussed also. Tire degradation will be accurately recreated within the game. It will be dependent on not only the driving of the gamer, but also the heat of the rubber.
Following the discussion of the tire degradation came the discussion of the damage of the cars themselves. There will be two different variations of damaging of the cars. With the regular cars within the game there will be damage to specific areas, along with scuffs and scratches to the body itself. When it comes to the Nascar and WRC vehicles it will feature full damage modeling. Meaning things will be fully destructible on the vehicle.
[Source]