France is a large country, two and a half times as big as Great Britain, extending for some 1,000 km/600 miSpain, and the Massif Central, which rises to over 1,800 m/6,000 ft in its southern and central parts. Consequently, there are considerable variations of climate within France. from north to south and from east to west. Although much of northern and western France is low-lying and rather flat, there are some high mountain regions in the south and east: part of the western Alps, the Pyrenees, which form the border with
Northern and northwestern France is most affected by the changeable weather brought in by Atlantic disturbances and its climate is rather similar to that of Britain.
Southern France has a Mediterranean-type climate and is warmer than the north, particularly in summer.
The high mountain areas have their own distinctive climates with heavier precipitation, much of it snow in winter; these areas are colder all the year round. Only along the Mediterranean coast and in the adjacent mountain regions is summer generally settled, sunny, and warm. Everywhere else in France the weather can be changeable at all times of the year.
It is most convenient for purposes of description to divide France into five climatic regions and to describe briefly the weather found in each.
Northern and Northwestern France
This area has the most maritime climate in all France. Winters are generally mild and frost and snow are not too frequent, becoming less so in the west. Rain occurs at all times of the year.
The summers are a little warmer than those found in southern Britain. Average daily hours of sunshine range from two in midwinter to between seven and eight in midsummer.
The summers are significantly warmer and sunnier than in northwestern France. They can be rather wet, particularly towards the Pyrenees and the Spanish border, but the rain tends to be heavy and of short duration. Summers have more sunshine and longer spells of settled weather than farther north.
Central and Eastern France
Winters become colder towards the east and they are not any warmer farther south. In winter occasional very cold spells can occur. There is a definite increase in summer warmth in the south and an increase in sunshine from an average of seven to nine hours a day. Compare the tables for Paris and Lyon.
The Mediterranean Coast and Corsica
Here summers are warm, or even hot, with a three-month period when rain rarely falls. When it does rain in this season it is heavy and often associated with thunder. Sunshine is abundant, as much as eleven to twelve hours a day in summer and five in midwinter.
Winters are generally mild and sunny but this pleasant weather is often interrupted by very changeable cold and blustery weather brought by a northerly wind called the mistral. This blows with particular strength in the Rhône valley and around Marseille.
The mistral can bring unseasonably cold weather for a few days in spring. The Côte d'Azur from Toulon to the Italian border, including the small independent principality of Monaco, is much less exposed to the cold blasts of the mistral and in Corsica the cold is moderated by the warm waters of the Mediterranean.
Corsica, which is particularly popular as a holiday resort because of its mild winters at sea level and hot sunny summers, is a mountainous island. In the interior altitudes exceed 2,000 m/6,500 ft and here winter snowfall can be heavy and snow cover may last well into spring.
The Mountainous Regions
These areas are the wettest and coldest regions of France and much of the winter precipitation is snow. Winter sports are best developed in the Alps and Pyrenees but can be pursued for a shorter period in the other mountain regions. The weather and climate of the French Alps and Jura is very similar to that found in the Swiss Alps.
Embrun illustrates conditions at medium levels in the heart of the French Alps. In the Pyrenees precipitation tends to be greatest in winter and autumn but in the Vosges, Jura, and the northern Alps, summer and autumn are the wettest seasons.
The southern Alps, Pyrenees, and parts of the Massif Central have relatively fine and rather warm summer weather, considering their height, but this may be briefly interrupted by cloud, rain, and thunder. The most unpleasant aspect of the summer weather in these mountain areas is the frequent and sudden onset of cloud towards midday, which may obscure the peaks but leave the valleys clear.
In winter, conditions are often reversed with the mountains rising into clear blue skies and the valleys enveloped in low cloud and fog. Severe frosts may occur in settled calm weather in all valley regions in winter.