Östersund has two distinct peak seasons and both are worth experiencing. Winter (December through March) brings reliable snow, excellent cross-country skiing on hundreds of kilometres of groomed tracks, the possibility of ice skating on Lake Storsjön when it freezes, and the cosy indoor culture that Swedes do better than almost anyone. The biathlon World Cup in November kicks off the winter sports calendar; December is the Christmas market and glögg season. The light is short but often extraordinary — clear cold days with low pink sun, and occasional northern lights.
Summer (June through August) brings long days, warm temperatures around 20–25°C, and the full outdoor programme: cycling on Frösön, boat trips on Storsjön, hiking in the surrounding fells. The Storsjöyran music festival in late July is Östersund's biggest annual event, a three-day outdoor festival on the lakefront that draws 20,000–30,000 people and has a strong Swedish and Nordic programme. Book accommodation well ahead for the festival weekend. Spring and autumn are quieter and have their own appeal — spring brings the melt and the arrival of migratory birds on the lake; autumn has excellent mushroom foraging in the surrounding forests.