In accordance with certain factors such as geographical location, influenced by the latitude and geographical elevation; the Alborz Mountain Ranges, its distance from the sea, the desert areas south of Turkmenistan, local winds and forest density, brings about a variable climate. In the northeast of the province, particularly to the east of the Caspian Sea and the distance between Gorgan Rood till the borders of Turkmenistan, due to non-influential affects of the Caspian Sea, decrease in the elevation of the eastern Alborz, the extension of the coastal plain and its proximity with the Qareh Qoum and Qezel Loun of Central Asia, a warm and dry climate is experienced. Where as this changes to a semi desert type in areas further off.
The annual rainfall is scarce in this area and due to this, the affect of the heat is overpowering. Thus bringing about a vast difference not only between daily maximum and minimum temperatures, but also seasonal differences, that is between the hottest and coldest month too. In the southwestern sector of the province, due to the presence of heights, such as in the cities of Kollaleh and Minoo Dasht, other changes in the climate are experienced and with the change of temperature, a moderate and humid climate prevails.