Spring
Late April to MayStrong all-round starting point. Long city walks, a Great Wall day, Xi'an heritage sites, Hangzhou blossoms and tea season, Nanjing flowers, and Chengdu, Chongqing, or Guangzhou city time without peak summer heat.
Plan around: Changing temperatures, Beijing and Xi'an wind, Shanghai, Hangzhou, Guangzhou, and Nanjing rain, basin humidity, Chongqing rain, and Labor Day demand.
Summer
June to AugustChoose for fixed school-holiday dates. Travelers who can start early, use indoor breaks, and keep weather slack.
Plan around: Beijing and Xi'an heat and rain; Shanghai plum rain and storms; Hangzhou and Nanjing heat, humidity, and rain; Guangzhou heat, humidity, rain, and possible tropical-cyclone effects; Chengdu and Chongqing heat, humidity, and heavy rain.
Autumn
September to early NovemberBest balance for many first trips. Outdoor-heavy itineraries, city walks, Great Wall scenery, Xi'an heritage sites, Hangzhou foliage and osmanthus, Nanjing foliage, Guangzhou's drier weather, and Chengdu or Chongqing day trips.
Plan around: National Day crowds, changing Great Wall conditions, early-season Shanghai or Guangzhou storms, short autumn windows in Hangzhou and Nanjing, autumn rain in Chongqing, and mountain microclimates around Xi'an, Chengdu, and Chongqing.
Winter
November to MarchA deliberate lower-season choice. Indoor culture, food, seasonal scenery, Guangzhou's mild city-break weather, and travelers comfortable with colder northern stops.
Plan around: Freezing wind and possible ice near Beijing and Xi'an; damp-feeling cold in Shanghai, Hangzhou, Nanjing, and Chengdu; cloud, fog, and variable visibility in Chongqing; sharp temperature changes in Guangzhou.