Best Season to travel: November to February.

What to wear: In summer light cottons during days and light woolens at nights are preferable. In winter, light woolens to heavy woolens depending on the region. Weather can change rapidly in mountains. It is therefore important to be suitably equipped.

Detailed Overview:

The geographical diversity of the state causes varied climatic conditions. The climate of Rajasthan can be divided into four seasons: Summer, monsoon, post‑monsoon and winter.

Summer: This is the period from April to June. The summer starts by mid-March and temperature starts rising progressively through April, May and June. The temperature ranges from 32 ºC to 45 ºC. In May and June, the dry western region of Rajasthan records a maximum temperature of 48 ºC.
On the other hand, Mt. Abu, the only hill station of Rajasthan (situated at the highest peak of the Aravali at an altitude of 1220 meters) registers the lowest temperatures ranging from 33 ºC to 23 ºC during this period.

Monsoon: This is the period from July to September. The monsoon arrives in late June in eastern and southern regions of the state and in mid-July in desert area. This period registers the maximum temperatures ranging from 29.5 ºC to 32.2 ºC in south and southeast of Rajasthan and an average of above 37.7 ºC in northern and northwestern regions. More than 90% of Rajasthan's rainfall occurs during this period. Humidity is high during this period, particularly in August.

Post-Monsoon: The monsoon generally ends by mid-September in all regions of the state and is followed by a second hot season during the months of October and November. This period records relatively uniform temperatures across the state. In October the average maximum temperature is 33 ºC to 38 ºC and the minimum is from 18 ºC to 20 ºC.

Winter: This is the season that attracts more tourists. Winter extends from December to March. This period records a considerable variation in maximum and minimum temperatures all over the state. January is the coldest month of the year. The minimum temperature falls to minus 2 ºC in the night at some places like Sikar, Churu, Pilani and Bikaner. A sharp decrease in night temperatures is experienced throughout the arid zone of western Rajasthan on account of quick release of thermal radiation from the sandy soil soon after the dark. The greater part of Rajasthan, except the south-eastern part of Kota, Bundi and Baran and the western district of Barmer records the average temperatures of above 10 oC. There is slight precipitation in the north and north eastern region of the state. Climate is pleasant during winter and this is the ideal time to travel. The most important thing is that a number of fairs and festivals take place during winter offering the traveler the best possible outlook of Rajasthani culture.