|Climatically, Rajasthan is the driest part of India. The Aravali Mountains stretching diagonally across the State from the South-West to North-East separate the desert and semi-desert areas to the West from the sub-humid areas in the East. However, the climate of Rajasthan can be divided into four seasons, namely summers, winters, monsoon and post-monsoon.
Summers in Rajasthan are a time of baking heat and hot winds. The summer season extends from April to June. The temperature during this period ranges anywhere between 32 to 45 degrees Celsius - in western Rajasthan, temperatures can reach as high as 48 degrees Celsius, especially in the months of May and June. It is only in the hill station of Rajasthan, Mt Abu, that one can expect some sort of respite from the hot weather. In the barren regions however temperature falls steeply at night. It is common in the summer months that heavy winds blow from the western boundary and bring dust storms, known as Andhi.
The monsoon brings relief to the hot and sun-baked terrain of Rajasthan during the month of June in the eastern region and mid- July in the western arid regions. The temperature drops from 40 to 35 degree. With the fall in temperature, humidity increases. The state receives approximately 90% of its annual rainfall during this season. There is a second phase of monsoon that continues from July to September.
The post-monsoon that commences from mid-September and continues till November. This season is once again characterized by heat and the average maximum temperature varies from 33 degrees C. to 38 degrees C. The average minimum temperature is between 17 degrees C and 20 degrees C.
Winter is the season with most favorable conditions and it is the best time for visiting Rajasthan. The glorious beauty of Rajasthan can really be experienced during this season. Winter in Rajasthan extends from December to March with January being the coldest month of the year. Temperature varies throughout the state and the lowest temperature recorded is 0 degree C. There is slight rainfall in the north and north eastern region of the state. On the average basis, winter temperatures range from 8° to 28° C (46° to 82° F).