I don't think that the sky will have changed much from how it is now, rain, snow, clouds
if there is water those stuff should exist too, it just depends on how hot it is. If it is really hot we could probably presume that it only rains at nights since the water evaporates too quickly in the sun.
If they make the worldmap big then maybe there could be some snow more up north (assumption is based upon f1,f2).
Anyway, I would like to see rain, snow, sunny, cloudy, night and day in the game, weather could be depending in which area you are in or if its night or day.