Haikou is on the northern edge of the torrid zone, and is part of the Intertropical Convergence Zone. April to October is the active period for tropical storms and typhoons, most of which occur between August and September. May to October is the rainy season with most rainfall coming in September. Despite its location, the city has a humid subtropical climate (Köppen Cwa), falling just short of a tropical climate. Nevertheless, the area has hot summers and warm winters, usually with high humidity. Extremes temperatures have ranged from 2.8 to 42.0 °C (37 to 108
