Total Eclipse (Weather Warden #9)

Weather Warden Joanne Baldwin, her husband, the djinn David, and the Earth herself have been poisoned by a substance that destroys the magic that keeps the world alive. The poison is destabilizing the entire balance of power, bestowing magic upon those who have never had it, and removing it from those who need it. It's just a matter of time before the delicate balance of nature explodes into chaos-and doom.