Iran has vastly varying climates depending on the season, and the part of the country. Generally speaking central Iran, being closed off from humidity of the seas by the surrounding mountains, has a distinctly continental climate. in winter though, a high-pressure belt centered in Siberia gushes westwards and south wards reaching the Iranian central plateau and at the same time low pressures develop over the warm waters of the Caspian, the Persian Gulf and the Mediterranean.
In summer, winds develop in parts of the country, specially the “summer wind” which sometimes reaches speeds of 100 km per hour. Warm wind blows from Arabia bringing with it high humidity from the Persian Gulf, to southern Iran.
Maximum and minimum temperatures are extreme, varying from 51C in Khuzistan in summer, to -37C in the north west, in winter.
Rainfall too varies considerably from one part of Iran to another. In the Caspian littoral the weather is relatively mild and rainfall high. Rainfall is lowest in the south-central regions.
In the west, the weather varies from cold in the north, becoming increasingly warmer- moving south wards. But on the whole, the weather in Iran is warm in the valleys and moderate on the mountains in summer; and moderate in the valleys and very cold on the mountains, in winter.
The southern coasts are generally I-rot and humid in summer, and mild and misty, sometimes with heavy fog, in winter.
as one moves from the north to the south and from the west to the east, the weather becomes warmer and the land more barren.