Climate Canary Islands
With good and stable weather guaranteed by the Azores high pressure system and sufficient humidity in the air carried by the trade winds, the Canary Islands have forged an image of land of eternal spring carefully promoted since the 1960s. If it is true that the oceanic subtropical climate of these islands allows to benefit from softened temperatures, by the ocean all year long, and by the trade winds in summer, they present nevertheless different microclimates, quite numerous and quite differentiated for such small spaces. There are semi-desert areas reminiscent of the Sahara in islands such as Lanzarote or Fuerteventura and mountainous areas with all shades of green in the center of La Gomera or the north of Tenerife, where it happens that the high mountain passes are closed due to snow. However, it is the sun that you have to watch out for, especially in the south.
Rain or no rain?
The observed climate will vary first of all according to the level of rainfall. In some western islands, they are more frequent and sometimes exceed 1,200 mm / year as in La Palma, but are considerably rare in the eastern islands such as Fuerteventura and Lanzarote, with less than 100 mm / year on the coasts and about 300 mm / year in the interior of these islands which have climates of arid semi-desert. This scarcity of rainwater has led to the installation of seawater desalination plants to supplement the water needs of islands or cities. It was Lanzarote that hosted the first desalination plant in the Canary Islands, but also in Spain, in 1964. They are still used in cities like Las Palmas de Gran Canaria or Santa Cruz de Tenerife. It is of course the mountains that play a major role in the rhythm of rainfall. Unlike the other islands, Lanzarote and Fuerteventura are rather low-lying islands as a whole and in general, rainfall increases with altitude. Therefore, water resources are significantly more important in the more mountainous islands such as Tenerife, La Palma or La Gomera. In concrete terms, the use of an umbrella will be rather rare during a trip to the Canaries, even if the rainfall increases in winter. On the other hand, these rains will influence the landscape, which will be greener in the parts concerned, generally the north of the islands and at high altitude.
Trade winds for ever
Another determining element for the climate of the Canaries is the almost continuous presence of trade winds. Coming from the northeast, these oceanic winds contribute first of all to the low thermal amplitude observed in the Canary Islands (outside of the altitude) by creating a "greenhouse" effect that filters the sun's rays onto the sea, thus maintaining the cold marine current that ensures the islands a milder temperature than they should have given their latitude. If they do not bring rain, these winds also contribute to the humidification of the crossed areas through a phenomenon called "mar de nubes", sea of clouds. This moisture is deposited on the vegetation, and then pine needles and laurel leaves drip onto the ground in surprising quantities, thus contributing to their own water supply. Another wind also affects some of the Canary Islands, the Calima. Loaded with sand and dust, this wind from the Sahara affects most logically Fuerteventura and Lanzarote, but can also reach Gran Canaria and Tenerife. The days of Calima lead to higher heat with white skies and reduced visibility. These mini sandstorms can last a few days and cause respiratory problems in the most sensitive people. Temperatures are rather high on average, but they do not vary much throughout the year, from a minimum of 18°C to a maximum of 28°C. July and August are the hottest months, but the temperature rarely exceeds 30°C. The weather cools down in winter, but the temperature does not fall below 15°C. The temperature also varies with altitude for all islands above 1,000 meters. Thus, the high mountain passes of La Palma and Tenerife may be closed in case of snow, and much more rarely, those of El Hierro and La Gomera. Very concretely, there will always be more sun in the south of each island, whatever the season. A sun whose power should not be forgotten, because many clinics in the south have made a fortune by treating the burns it can cause. To make tourists aware of this, Santa Cruz de Tenerife inaugurated in 2017 the first "red light" of the sun that informs them in real time of the exact degree of sun exposure and has been followed by other municipalities such as Puerto del Rosario, in Fuerteventura.
