Equatorial Guinea has a tropical climate with distinct wet and dry
seasons. From June to August, Río Muni is dry and Bioko wet; from
December to February, the reverse occurs. In between there is gradual
transition. Rain or mist occurs daily on Annobón, where a cloudless day
has never been registered. The temperature at Malabo, Bioko, ranges from
16 °C (61 °F) to 33 °C (91 °F), though on the southern Moka Plateau
normal high temperatures are only 21 °C (70 °F). In Río Muni, the
average temperature is about 27 °C (81 °F). Annual rainfall varies from
1,930 mm (76 in) at Malabo to 10,920 mm (430 in)) at Ureka, Bioko, but
Río Muni is somewhat drier.