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 obtains. 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 to 33° C (61– 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 (80° F ). Annual rainfall varies from 193 cm (76 in) at Malabo to 1,092 cm (430 in) at Ureka, Bioko, but Río Muni is somewhat drier.