India’s climate encompasses a wide range of weather conditions across a vast geographic scale and varied topography, making it hard to generalise. India plays host to 6 major climatic sub-types, from arid desert in the west, alpine tundra and glaciers in the north, and humid tropical regions supporting rainforests in the southwest and the island territories, based on the Köppen system. Many regions have entirely different microclimates. There are 4 seasons – winter January and February; summer March to May; a monsoon (rainy) season June-September; and a post-monsoon period October to December.
India’s unique geography and geology heavily influence its climate. This is especially true of the Himalayas in the north and the Thar Desert in the northwest. The Himalayas obstruct the extremely cold katabatic winds coming in that blow down from Central Asia. Hence, North India is kept warm or only mildly cooled during the winter season. In the summer months, the same phenomenon makes India pretty hot. Although the Tropic of Cancer, the boundary between the tropics and subtropics, runs through the middle of India, the entire country is considered to be tropical.
As is common throughout much of the tropics, the monsoon and other weather conditions in India are unstable – huge droughts, floods, earthquakes, cyclones and other natural disasters are infrequent, but have killed or displaced millions.
The climate is of major importance when deciding when to visit India. Bear in mind that there is a distinct difference in climatic conditions in the far north to those of the extreme south. Although there are of course 4 seasons, generally, India’s climate is defined by 3 seasons – the hot, the wet (monsoon) and the cool, each of which may differ in duration from north to south. The most pleasant time to visit most places is during the cooler period from November to roughly mid-February.
The Hot Season
The heat starts to gather on India’s northern plains from around February, by April or May it gets really hot, with the hottest time being June. Temperatures of 45°C and above are common in central India. During these months South India also becomes extremely hot, sometimes unbearably so! Late in May the first signs of the monsoon appear in some areas – high humidity, electrical storms, short rainstorms and dust storms that turn the day as dark as night. The hot season is the time to leave the plains behind, heading for the cooler hills. This is when hill stations are at their best – and busiest!
The Monsoon Season
When the monsoon fully arrives, the rain falls steadily, usually starting the beginning of June in the extreme south, then spreading north to cover the whole country by early July. The main monsoon comes from the southwest, but the southeast coast – and southern Kerala – are mainly affected by the short and astoundingly wet northeast monsoon, which brings rain from around October to early December. Things don’t really cool down though – hot, dry, dusty weather is merely replaced by hot, humid and muddy conditions. It doesn’t rain all day, but usually it does rain every day. Followed by the sun this makes for a tiring steam room environment.