<P> In France, it refers to a violent, cold, north or northwest wind that accelerates when it passes through the valleys of the Rhône and the Durance Rivers to the coast of the Mediterranean around the Camargue region . It affects the northeast of the plain of Languedoc and Provence to the east of Toulon, where it is felt as a strong west wind . It has a major influence all along the Mediterranean coast of France, and often causes sudden storms in the Mediterranean between Corsica and the Balearic Islands . </P> <P> The name mistral comes from the Languedoc dialect of the Occitan and means "masterly". The same wind is called mistrau in the Provençal variant of Occitan, mestral in Catalan, maestrale in Italian and Corsican, maistràle or bentu maestru in Sardinian, and majjistral in Maltese . </P> <P> The mistral is usually accompanied by clear, fresh weather, and it plays an important role in creating the climate of Provence . It can reach speeds of more than 90 km / h (56 mph), particularly in the Rhône Valley . Its average speed during the day can reach about 50 km / h (31 mph), calming noticeably at night . The mistral usually blows in winter or spring, though it occurs in all seasons . It sometimes lasts only one or two days, frequently lasts several days, and sometimes lasts more than a week . </P> <P> The mistral takes place each time there is an anticyclone, or area of high pressure, in the Bay of Biscay, and an area of low pressure around the Gulf of Genoa . When this happens, the flow of air between the high and low pressure areas draws in a current of cold air from the north which accelerates through the lower elevations between the foothills of the Alps and the Cevennes . The conditions for a mistral are even more favorable when a cold rainy front has crossed France from the northwest to the southeast as far as the Mediterranean . This cold, dry wind usually causes a period of cloudless skies and luminous sunshine, which gives the mistral its reputation for making the sky especially clear . There is also, however, the mistral noir, which brings clouds and rain . The mistral noir occurs when the Azores High is extended and draws in unusually moist air from the northwest . </P>

When do the mistral winds blow in provence