Hanzhong has a humid subtropical climate, significantly warmer and wetter than the rest of Shaanxi. Winters are mild by Chinese standards — rarely dropping below freezing in the valley floor — and summers are hot and humid. The Qinling Mountains to the north block cold winter winds and trap monsoon moisture.
Spring (March–April) is the peak tourist season, when the rapeseed fields are in bloom across the Han River valley. Accommodation fills up on weekends during this period and prices rise. Book ahead.
Autumn (September–November) is the other good season: cooler temperatures, clear skies, and the trees of the Qinling slopes changing colour. The Three Kingdoms sites are at their most atmospheric.
Summer (June–August) is hot, humid, and often rainy. The mountain scenery remains attractive but the valley heat can be enervating. Winter (December–February) is the quietest and cheapest time; the historical sites are largely uncrowded and the climate is tolerable, though some mountain roads may close after snowfall.