Climate

The Southern Rhône is dominated by the Mediterranean climate.
Average::
Sunny hours: 2300 per year
Rainfall: 750 mm per year - 80 days
Mistral: 180 days a year

Precipitation in Provence are usually short in time and often accompagned by thunder. It often takes place during the nights and can be dramatic and can cost some overfloading. This happened just before the harvest in 2002 and spoiled the quality of the harvest.
The rainfalls in the growing season are normally moderate and the sun and the mistral can in must cases dry the green parts of the vines and prevent fungal diseases.
Probably dry periods cost more problems for the quality of the wines of Chateauneuf du Pape than too much rain and it's not allowed to irrigate the fields.

Sunshine is the basic creator of plants and grapes as it allows the photosynthesis - together with minerals and water - to develop the green parts of the plants and the grapes.
There are lots of sunshine in the Southern Rhone valley. So many days with high temperatures that not all grape varieties can be succesful there. It's not a coincidence that you don't see the grapes from Bourgogne or Bordeaux here. Generations of experience have learnt the wine growers which grapes were suitable for the climate. Especially Grenache reaches it's peak here in sunny Chateauneuf.
This climate brings a high degree of alcohol to the wines. As a wine grower once said: "We never write more than 15% on the label". About 14% are very common.

The mistral is the name of the often quite strong wind always coming from the North down through the valley. It can blow all year round in shorter or longer periods. For human beings it can be irritating if it blows for many days.
For the vines the mistral can be damaging if it's extraordinary strong especially during flowering og harvest. The most used pruning method gobelet helps prevent damage. In all the mistral is very good for the vines as it prevents fungis disease and in the period of harvest concentrate the grapes. Too much water on or in the grapes doesn't bring quality to the wines.
The wind also prevents attacks from insects.
The white on black numbers on the figure to the right show the constant force of the mistral and the red on black numbers tells about the force in gusts (km/h).