Climate
The Mediterranean climate is characterized by long, hot summers and cool, dry winters, with few days of frost, but even in the garrigues, winters are colder. As soon as you reach the Cévennes and approach Mont Lozère, summers are shorter and more temperate, and winters can be harsh depending on altitude. From June to September, daily temperatures rise above 25°C during the day, and exceed 30°C at the height of summer, while rain is rare and only falls in sudden thunderstorms. While in the south of the département, the minimum night-time temperature rarely drops below 17°C at this time of year, it's sometimes a good idea to cover your shoulders in the evening when you're further north.
Even so, there are 2,700 hours of sunshine a year, compared with a national average of less than 2,000 hours. Mediterranean rainfall is infrequent but abundant. Rainfall of 100 millimetres in a single day is not exceptional, and 300 millimetres can easily fall in two or three days in spring and autumn, the two main rainy seasons in the Midi. In the southern garrigues, annual rainfall varies between 700 and 800 millimetres, rising to 1000 millimetres towards Alès. In the Cévennes, annual rainfall ranges from 1,300 to 1,700 millimetres.
While meteorologists are baffled by the layout of the mountains in the Cévennes foothills, with the orientation of each valley and its exposure completely changing the climatic data, no mountain escapes the phenomenon of "Cévennes episodes", generally around the equinoxes. Powerful winds and strong thunderstorms, the violence of the rainfall causes sudden and devastating floods, notably those of the Gardons known as "gardonnades". The intensity of these episodes can last for two or three days, during which time all you can do is wait in a sheltered spot, and hope the damage isn't too extensive..
The "ven", or south wind, is mild and humid, bringing clouds and rain from the Mediterranean. When it veers southeast, it's called "le grec", "le marin de Beaucaire" or "vent de miejour" in the mountains. The mistral, "mistraou" or "maestral", which comes from the north down the Rhone valley, can be very cold, but it's the mistral that blows the clouds away. The tramontane, which arrives from the west and blows between the Pyrenees and the southern Massif Central, is called "trabès", "traverse", "roudergue", "l'auvergnat" or "narbouné". The easterly wind, "l'aigalas" or "ajalas", is feared in winter and comes with a somewhat overrated reputation as a tireless blower. The proverbial Aigalas bouffo es pas jamaïs las means "the aigalas blows and is never weary".
Characteristic landforms and landscapes
The Camargue
The south of the département is made up of farmland, marshland and a small but magnificent 23 km coastline along the Mediterranean, with the Hérault on one side and the Bouches-du-Rhône on the other. Vauvert, Saint-Gilles, Le Grau-du-Roi, Aigues-Mortes and Port-Camargue have an authentic charm that rivals that of neighboring La Grande-Motte and Saintes-Maries-de-la-Mer. The beautiful Pointe de l'Espiguette, a dune beach 10 km long and 2 to 4 km wide, forms the boundary between the lagoons and the Mediterranean. The plain dominates here, as far as the ponds south of Nîmes.
The Costières
After the Camargue, the Costières are the most prominent relief in the Gard. Its hills, between 80 and 100 m in altitude, culminating in the Puech de Dardaillon forest massif (146 m) at Générac, dominate Nîmes to the south. A small territory 40 km long, between the communes of Beaucaire and Vauvert, its panorama offers a view of the Cévennes and the Alpilles. It is well known for its costières-de-nîmes appellation contrôlée wine, registered only since 1986, but renowned since the Middle Ages, strongly marked by the stony soil on which its grapes grow. The same type of hills can be found in and around Quissac and Lédignan, where much of the land is also devoted to winegrowing.
The Garrigues
Between the towns of Bagnols-sur-Cèze in the far east, Vézénobres in the west and Nîmes in the south, in the north-east of the Gard region, there is a succession of faulted plateaus and hills, made of limestone of varying hardness, often shallow and poor in humus. The vegetation that grows here is typical of dry environments, rich and particularly resistant to high temperatures, known as "garrigue". Garrigues can be massive, with relatively gentle slopes interspersed with steep slopes, or asymmetrical and steep. They alternate with the surrounding plains and cultivated alluvial basins.
Causses and Cévennes
Mont Aigoual, at 1,567 m, is the highest point in the Gard region of this ancient chain of elongated hills and mountains with long, narrow ridges. From Le Vigan to Génolhac, via Sumène, Saint-André-de-Valborgne, Saint-Jean-du-Gard and La Grand-Combe, the roads are built on schist and granite. Anduze and Alès are considered the gateways to the Cévennes. The causses, imposing limestone masses of the surrounding plateaux, hollowed out and fragmented by alkaline sediments, rest on the crystalline massif. At the western end of the Gard department, the Causse de Blandas offers breathtaking views of the Cirque de Navacelles.
Hydrography
Small rivers such as the Hérault and Vidourle, which flow from the Cévennes through the Garrigues into the Mediterranean, are fed by a large number of very irregularly-flowing streams. These in turn are fed by small streams, subject to heavy rainfall. These mineralized waters also flow through networks of natural underground galleries and caves. Several rivers named Gardon flow through the Cévennes valleys, and are distinguished by the villages they pass through: Gardon de Saint-André, Gardon de Saint-Jean, Gardon du Mialet, etc. The smaller Gardons form the larger Gardons, that of Anduze and that of Alès, which eventually unite to form Le Gardon. The Gardon flows under the Pont du Gard to join the Rhône at Vallabrègues. The Cèze rises in Lozère at Saint-André-Capcèze, on the border of the département, swells with mountain streams and ends its course in the Rhône.
