Stormqueen!
Marion Zimmer Bradley
 The novel is set in Darkover's Ages of Chaos where feuding families, the Elhalyn and the Ridenow, are engaged in a breeding scheme to develop children with frightening psychic powers, called laran. The main protagonist is Dorilys Aldaran, the heir to the Rockraven line who develops a fearsome power to alter the planet's weather patterns.