The South Asian country is no stranger to scorching summers but years of scientific research has found climate change is causing heatwaves to become longer, more frequent and more intense.

The Indian Meteorological Department predicted four to five additional heatwave days in the western states of Gujarat and Maharashtra, and regions along the eastern coast, in the coming weeks.

"There will be an increased number of heatwave conditions along the east coast states and Gujarat by about four to five days in the month of May," IMD chief Mrutyunjay Mohapatra told reporters.

Temperatures could run three to five degrees Celsius above normal during peak spells in some of those areas, Mohapatra said.

At the same time, the heat is likely to be fairly moderate in India's northern and central regions.

India usually experiences four to seven heatwave days between April and June.

Infants, the elderly, people with existing health problems and outdoor workers are particularly vulnerable to hotter temperatures.

The resulting heat stress can cause symptoms ranging from dizziness and headaches to organ failure, and even death.

City dwellers surrounded by concrete, brick and other heat-absorbing surfaces also face an elevated risk.

Prolonged periods of extreme heat can also strain infrastructure such as power grids and transportation systems.

The weather agency also forecast above-normal rainfall in May, with precipitation expected to exceed 110 percent of the long-term average.