Summer (June through August) is the best time to visit. Days are long and warm, the river is running well for floating, and the farmers' market and outdoor culture are in full swing. Temperatures can reach the low 30s Celsius in July and August.
Autumn is excellent for hiking: cooler temperatures, little rain, and the larch trees in the mountains turn gold in late September. Winter brings reliable snow and cross-country skiing at Rattlesnake or downhill at Snowbowl (20 minutes from town). Spring is wet but the mountains are still skiing well into April.