A different climate between the north and the south

In Tunisia's coastal regions, the climate is mild in spring and autumn, and warmer in summer, with a sea breeze on the beaches. Bathing is possible until October or even November. In the north, it rains quite often in winter and spring, and it can also be a few degrees below 0 in the Kroumirie mountains. In the south, it's extremely hot and dry in summer - with temperatures sometimes climbing to around 50°C in the shade - but nights can be a little chilly. Temperatures are very pleasant in spring. The best time to visit the south is in winter, when, despite the cool nights, you can enjoy beautiful sunny days, ideal for strolling through the oases or the desert. Unfortunately, since the 2000s, Tunisia has been suffering from an overwhelming drought. In the south, it's not uncommon to see the little greenery that was already struggling to develop scorch away.

Annual rainfall varies from region to region: in the north, from 800 mm to 1,000 mm; in the south, from 50 mm to 150 mm. Rainfall is irregular, concentrated during the cold season (75% of the annual total). The summer season's considerable aridity is mainly due to the sirocco. Average temperatures are 30°C in July and 12°C in December. The country also enjoys over 3,000 hours of sunshine a year.

August 2021: extreme temperature record

Summer 2021 hit the headlines with scorching temperatures in many parts of the world. Tunisia was not to be outdone: on August 11, 2021, the record temperature was reached in the governorate of Kairouan, in the center-east of the country. Tunisia's National Institute of Meteorology (INM) recorded a temperature of 50.3°C, close to the record for the African continent (51.3°C in Ouargla, Algeria, in 2018). The previous such extreme temperature in Tunisia dates back to July 26, 2005, with 50.1°C at El Borma in the south of the country. On this day in August 2021, INM also reported that temperature records had been broken in several cities: Sfax (45.8°C vs. 47.7°C in 2005); Nabeul (46.3°C vs. 45.5°C in 2018); Sidi Bouzid (47.4°C vs. 46.8°C in 1960). This is clearly a sign of global warming, and of phenomena that are likely to recur more and more each year.

The five bioclimatic zones in Tunisia according to Emberger

Louis Emberger (1897-1969), a French botanist, created the Emberger quotient, an index that classifies high-mountain aridity zones (only Morocco includes them all). This quotient or index takes into account observations made on vegetation as a function of rainfall and temperatures in a given zone. Thus, the map of Tunisia's five bioclimatic zones, published post-mortem in 1975, logically shows that the country is wetter in the north and arid in the south with the Sahara.

The time of the grenadines

At the end of September and beginning of October, a mild heat returns to the whole country, which had begun to lose slight degrees day by day. This is known as the "grenadine season". The vagaries of the weather help the good big pomegranates to finish ripening, so that they can be found on the market and enjoyed. The thermometer can then resume its gentle plunge, ushering in winter.