It's impossible to pin down the best time to visit India with such a wide range of climatic factors. Broadly speaking October to March tend to be the most pleasant months over much of the country. In the far south, the monsoonal weather pattern tends to make January to September more pleasant, while Sikkim and the areas of northeastern India tend to be more palatable between March and August, and Kashmir the mountainous regions of Himachal Pradesh are at their most accessible between May and September. The deserts of Rajasthan and the northwestern Indian himalayan region are at their best during the monsoon. The trekking season in the Indian himalaya runs roughly from April to November, though this varies widely depending on the trek, altitude and region. The Ski season is between January and March.

Usually people visit India during the months of September to March, when the weather is pleasant and perfect to roam around. However, the months of December and January can be bone chilling so it is advised that you carry woolens with you. September is usually the time when it stops pouring in most of India and the weather is pleasant, though a bit humid. The southern part of India experiences winter monsoons so it is pouring out there in the months of November and December. The south of India hardly experiences any winter. The weather is warm and may get slightly chilly in the night.

Another reason to visit India in these months is that they coincide with the celebration mood in India. This is the time when maximum well-known festivals of India are celebrated. In October - November falls Dussehra, Durga Puja and Diwali. Also in November is the Pushkar Fair (in Rajasthan), the largest cattle fair in India. In January is the Republic Day of India and Lohri - the festival of Punjabis. In March falls Holi, the festival of colors. Then there is Id, Easter, Christmas and a number of another festivals, each celebrated in totally Indian fashion. You can experience true India, in all its richness, by attending these festivals.

The summer months of March to May are very hot and humid. If you are planning to visit India during summers, then the best thing is to go to the hills and enjoy the scenic beauty. If you are interested in trekking or mountain climbing, then, the Himalayas are for you. Months of March to May, September and November are ideal for trekking in the Himalayas.