Although Iran is situated in the northern temperate zone, it has diverse climatic conditions due to various reasons. The direction of its mountains, its being adjacent to the hot and arid Saudi Arabian deserts, and its distance from the seas is the most important reasons behind Iran's diverse climatic conditions. 

One distinct climatic feature of Iran is the intense temperature gradients, which at certain instances exceed 40 degrees centigrade (104°F). The warmest areas of the country are the coastal regions of the Persian Gulf and the Sea of Oman as well as the pits in Loute and Sistan.In the summertime, the temperature in these areas exceeds 45 degrees centigrade (113°F). This is while the temperature in the northwestern and western parts of the country as well as the northern mountainous areas may reach over minus 30 degrees centigrade (-22 °F) in winters. It must also be noted that the annual precipitation level varies from zero to 2000 millimeters. The highest level of annual precipitation takes place in the Caspian Sea coastal areas as well as the northern and northwestern parts of the country. The lowest level of annual precipitation takes place in the southern and eastern parts of the country and the central desert region. 

Classification of the climates: