Spain is one of the warmest countries in Western Europe. For Spain is characterized by very deep internal climatic differences, and it is only conditionally can be entirely attributed to the Mediterranean climatic region. In the far north-west the climate is mild and humid with weak fluctuations in temperature throughout the year and high rainfall. Constant winds from the Atlantic bring a lot of moisture, especially in winter, when the dominant misty and cloudy weather with drizzling rain, with little frost and snow. The average temperature of the coldest month is the same as in the north-west of France. Summers are hot and humid, average temperatures rarely below 16 degrees Celsius. Quite different conditions in the interior parts of the country - on the plateau of the Old and New Castile and Aragon plain. In these areas, the influence of plateau-hollow of a relief, a considerable height and the local continental air. In Old Castile and Aragon are quite plain cold winters with frosts and strong, harsh winds, hot summers and fairly dry, although the maximum precipitation occurs in this season of the year. In New Castile climate is slightly softer, with more warm in winter, but also with low rainfall. Agriculture in all these areas need irrigation/