From Tar Valon Library
Cloud Dancing is the talent that allows a person to control the weather (TPoD, Ch. 16). The talent is more developed in the current age than in the Age of Legends, at which time, ter'angreal such as the Bowl of the Winds were required to achieve what people with the skill were able to do on their own (TPoD, Ch. 2). Caire was able to use her ability at Cloud Dancing, along with the Bowl, to overcome the Dark One's touch on the world and fix the weather (TPoD, Ch. 5). The ability to control the weather varies greatly, some are very poor at it (TFoH, Ch. 30). Ability in the talent seems to be something Aes Sedai know about each other, at least if they have great strength, as Romanda knew that none of the Aes Sedai in Ebou Dar had much ability (TPoD, Ch. 16).