Changsha has a humid subtropical climate: hot and humid summers (June-August, often above 35°C), mild springs and autumns, and cold winters that occasionally see snow. Spring (April-May) and autumn (September-October) are the most comfortable times to visit. Autumn is particularly recommended: the ginkgo and maple trees on Yuelu Mountain turn gold and red in October-November, the museum crowds thin slightly after Golden Week, and the temperature is ideal for walking the city.
Summer is relentlessly hot and humid but the city operates at full energy — food culture, nightlife, and events peak. If you can tolerate the heat, the experience is authentic. Winter (December-February) is cold and grey but quieter; the Hunan Provincial Museum and indoor attractions are comfortable year-round. Chinese national holidays (Golden Week in October, Spring Festival in January-February) bring massive domestic tourist crowds; book accommodation and transport well in advance if visiting then.