Zhangjiakou's winters are harsh, with temperatures often dropping below -26°C in January and averaging around -7°C. Spring brings a gradual warming trend, with temperatures rising to as high as 27°C by April. Summer is warm and humid, with highs reaching up to 34°C from June to August. Autumn is generally mild, with temperatures ranging from around 8°C to 22°C in September and October. In contrast, winters are cold and snowy, with January being the coldest month of the year.