Very pleasant temperatures
Cape Verde enjoys moderate temperatures thanks to the cold Atlantic currents that bring pleasant weather and humidity. In comparison: the air temperature is cooler than in Senegal, and the sea is warmer. Humidity levels vary between 40% and 60%. The ocean and trade winds moderate temperatures. The annual average rarely exceeds 25°C and never falls below 20°C. Water temperatures range from 21°C in February to 25°C in September.
Wind in the sails
Throughout the year, the lives of its inhabitants are governed by omnipotent winds: trade winds, monsoons and the dreaded harmattan. Landlocked in a Sahelian zone, between the 14° parallel (at Mauritania) and the 17° (at Dakar) in dry tropical latitudes, Cape Verde is a marine extension of the Sahara and, like it, is subject to very dry air masses. The north-easterly trade winds blow non-stop between December and April, peaking at the beginning of the year, much to the delight of kiteboarders. Regrettably, however, these winds produce so little humidity that only peaks of 600 m or more can benefit from the salutary rainwater. The highest peaks, on Fogo, Santo Antão and Brava, can spend most of the year with their heads in the clouds. In addition to this benevolent wind, which limits the feeling of tropical heat, there are two other atmospheric factors. The first is the harmattan, a hot, dry desert wind that gusts from October to June, causing bruma seca, an ochre-coloured sand dust that fills the air and brings flights to a halt.
The second factor is the south-western summer monsoon, which brings the long-awaited rains between August and October, sometimes with heavy showers. Around mid-August, the first dark clouds appear, but you have to wait until September to enjoy this liberating coolness. Half the year's rainfall can sometimes fall in a single violent storm. Unfortunately, Cape Verde is a little too far north for systematic rainfall: it lies just above the doldrums, where the north-east and south-west trade winds converge and rain is guaranteed.
Repeated droughts and uncertain rains
The longest recorded period during which Cape Verde has not been watered by the summer monsoon is 18 years. For 12 years from 1968, there was another interminable drought. The rainfall figures tell an equally strange story, namely the wide variation in rainfall, inequitably distributed, between the slopes of the same island. On Fogo, the 35-year average rainfall for the northeast slope of Monte Velha is 1,190 mm, while on its leeward side it is 167 mm. Rain can also fall on an island over a very short period: 20 years ago, 3,000 mm of rain fell in a single month. The lower islands of São Vicente and Santa Luzia receive much less moisture, making them almost totally desolate and barren. Not to mention the phenomenon of global warming, which disrupts the normal rhythm of the seasons.
