Climate in India varies from region to region. The Himalaya and the Thar Desert play contributing roles in India's climate. Meteorologically, climate of India has been categorized into seven climatic regions; the Himalayas, Assam and West Bengal, the Indo-Gangetic Plain, the Western Ghats and coast, the Deccan and the Eastern Ghats and coast.
Generally, India climate experiences summer from March to June, rainfalls from June to October and winter from November to March. Northwestern regions of India have summer season from April to July and the other parts from March to June. April gets hotter in the Western and Southern India and May in the northern parts. In the coastal regions temperature usually gets around 36C in summer.
Ladakh and Zanskar, Spiti, northern Kinnaur and some areas of northern Uttaranchal has low humidity most of the time, not more than a few centimeters of rainfall a year with occasional heavy rainstorms during July and September and the coldest temperatures found anywhere in the world during the winter season.
Climatically, these regions are most travel-friendly in September. In case of the Kashmir Valley and the lower Warvan and Chenab valleys in Jammu and Lahaul, April and May bring about heavy precipitation, months from December to March experience heavy snow falls and the months from May to mid-October are comparably more favorable for traveling.
During November and December the states of Tamil Nadu, Karnataka, and Kerala experience most of their rainfall from the northeast monsoon whereas 80 percent of the country receives most of its rainfall from the southwest monsoon from June to September. Most ideal time for traveling to India is during October to April, when temperatures being less hot are comparatively favorable for travelers.