Kofu's winters are cold and variable, with temperatures often plummeting below -30°C in January and February. Spring is a gradual warming period, with March and April experiencing mild temperatures around 5-7°C on average. Summer months of June to August bring warm to hot conditions, with July and August averaging around 21°C, while September's temperature drops back down to autumnal levels. Autumn brings cooler temperatures, with November and December experiencing cold snaps, mirroring the winter lows.