The Mountains of Channadran Winter King's War #3 Susan Dexter Del Rey Books 1986
Tristan, apprentice wizard and King of Calandra, should have found peace. His finding of the lost Sword of Calandra and his crowning should have ended the doom that held the land in its grip.
But Nimir, Lord of Ice and Storm, still held Calandra fast. It was summer, but crops were dying under cold and snow, and starvation threatened all. Tristan and his beloved Elisena could only save the land by daring the fearful trip into the ice-clad Mountains of Channadran, to face and try to destroy Nimir at the seat of his power.
It was an impossible feat but they had no other choice. And in his bird-filled, mysterious tower, Royston Ambere awaited a hero, while his daughter Welslin, known as Fateweaver, held her stony heart for the one man who could claim it. Nimir gathered his forces and prepared his deceits.