Visit Rajasthan sometime between September to February.. The weather is pleasant and not very cold during November and February. Also, if to want to explore Udaipur at its best, visit sometime during the monsoon. The greenery is breathtaking during that time.
Recently i had my trip in Rajasthan... That was between 24th jan to 24th feb... Climate was very good... Nights are much colder, which can go as low as 5 degree... Day time its around 20s...
The best will be October to mid February (Mainly winter only). As it a dessert area and in summer it is too hot to handle. So I'll suggest you to plan Rajasthan trip in upcoming October. thanks
Best time to visit Rajasthan is in winter season during Oct-Mar or in rainy season during during Aug-Sept in Summer visiting Rajasthan is not preferred by the visitors as mostly all of the places have 40+ degree celcius temperature and some places even reach 50 degree celcius temperature so it becomes impossible to go out during day time. thanks.
Winter season the best season to visit Rajasthan as it's a desert place so summer would be harsh and there might be hot in monsoon as well. So winter can be consider as the best season.
Plan accordingly.