Weather locations in Comoros

The Comoros is an archipelago of three large volcanic islands in the Mozambique Channel, at the northern end of the channel that links the Indian Ocean to Africa. The islands are small, steep and heavily ringed by mountain slopes, so the climate is tropical and maritime with only mild seasonal variation. Because there is little level land, rain depends closely on which slope the trade winds or the monsoon happen to be hitting, and conditions can change within a few hundred metres.

Main climate types

The islands carry an equatorial to tropical rainforest climate in the Köppen scheme, meeting the tropical savanna grade on the driest leeward lowlands of Grande Comore. The windward side of each island has a perhumid climate that can receive rain on most days of the wet season, while the sheltered coastal strips stay semi-arid for months.

Temperatures

Temperatures are very stable. Moroni averages about 26 °C in January and about 25 °C in July, the coolest month, with daytime highs in the low 30s °C and nights rarely falling below 20 °C. The sea and the surrounding water keep the air comfortably warm, and the highest summits, several of which are over 1,500 metres, grow noticeably cooler with cloud.

Rainfall

Annual rainfall ranges from under 1,000 mm on the most sheltered coastal ground of Grande Comore to about 2,000 mm or more on the windward slopes of Anjouan and Mayotte. Rain comes in two broad phases: a wetter period driven by the south-west monsoon around December to April, and a second, lighter peak under the south-east trades from about May to October. Cyclones forming in the channel between November and April can bring wind and heavy rain.

When to go

The cooler, driest months are usually August to October, when the south-east trades are at their strongest and sea conditions are best for swimming and snorkelling. The cyclone months from December to March carry the greatest risk of storms and rough seas.