Ajmer has a desert climate so expect extremely hot summers and chilly winters. Summer occurs between April and June and the average temperature is about 45 degree Celsius. During winter (November to February) it is a bit cooler and during the monsoon season (March) the city is transformed into a green haven. The best time to visit Ajmer is when it is cooler, so go between October and March. Avoid the hectic desert heat, if you are not used to it, can make you sick (the last thing you want on a holiday).