Dali sits at 2,000 metres and is famous in China for its mild climate — locals call it the city of 'wind, flowers, snow, and moon'. It is comfortable to visit any time of year, but the seasons differ.
March to May is arguably the best — clear skies, wildflowers on Cangshan, water and air both pleasant. June to August is the wet season, with afternoon thunderstorms and occasional heavy rain; it is also the warmest and the busiest, as Chinese domestic tourism peaks. September to November is mild and dry, with good visibility for mountain views. December to February is cool but not cold — daytime temperatures around 12–15°C, dropping toward freezing at night. Snow occasionally dusts the Cangshan summits in winter, which is the source of the 'snow' in the local motto.
Avoid the Chinese national holidays — May Day (1–5 May), National Day (1–7 October), and Lunar New Year — when the old town is packed and accommodation triples in price.