Viktor Blomberg: Rock Solid Studios-
The weather system is also a lot more complex than the weather seen in most other engines. You can watch the mist rise in the valleys on a starlit night when the terrain cools off after a rainy day, or look for the rainbow in the front of a coming thunderstorm, or get caught in a blizzard while trying to climb a mountain, etc. The clouds are created procedurally based on a number of factors such as temperature, humidity and time of day. The fact that they are created procedurally means that if two players in a world stand at the same place at the same time, they will both experience the same weather.