• India is expected to experience hotter-than-usual temperatures from April to June, with more heatwave days in central and eastern India and the northwestern plains, India Meteorological Department (IMD) chief Mrutyunjay Mohapatra said on March 31.

• Most parts of north and east India, central India, and the plains of northwest India are expected to experience two to four more heatwave days than normal. Usually, India records four to seven heatwave days from April to June.

• Some states, including eastern Uttar Pradesh, Jharkhand, Chhattisgarh and Odisha, are expected to have 10 to 11 heatwave days during this period.

• In April, most parts of India will likely witness higher-than-usual maximum temperatures. However, some areas in the extreme southern and the northwestern regions may experience normal temperatures.

• States likely to see above-normal heatwave days include Rajasthan, Gujarat, Haryana, Punjab, Madhya Pradesh, Maharashtra, Uttar Pradesh, Bihar, Jharkhand, West Bengal, Odisha, Chhattisgarh, Telangana, Andhra Pradesh and the northern parts of Karnataka and Tamil Nadu.

• Minimum temperatures will be higher than usual across most of the country, except for a few places in the northwest and the northeast where temperatures may be normal or slightly below normal.

• India experienced an exceptionally harsh summer in 2024, recording 536 heatwave days, the highest in 14 years, according to the IMD.

• Official data showed that India recorded 41,789 suspected heat stroke cases and 143 heat-related deaths during one of its hottest and longest heat waves.

• Experts have said India might be undercounting heat-related deaths due to lack of robust data.

• The heatwave arrived much earlier in 2025 than last year. In 2024, India reported its first heatwave in Odisha on April 5 but parts of the Konkan and coastal Karnataka experienced heat waves as early as February 27-28 this year.

• Mohapatra also warned that landslides could occur in parts of Kerala and Karnataka in the Western Ghats and that northeastern states might face flooding in April. 

What is a heatwave?

• Higher daily peak temperatures and longer, more intense heatwaves are becoming increasingly frequent globally due to climate change. India too is feeling the impact of climate change in terms of increased instances of heatwaves which are more intense in nature with each passing year, and have a devastating impact on human health thereby increasing the number of heatwave casualties.

• Heatwaves do not fetch as much public attention as more dramatic disasters such as earthquakes and floods, but until more recently they were taking a substantial toll of lives in India.

• A heatwave is a period of abnormally high temperatures, more than the normal maximum temperature that occurs during the summer season. 

• Heatwaves typically occur between March and June, and in some rare cases even extend till July. 

• The extreme temperatures and resultant atmospheric conditions adversely affect people as they cause physiological stress, sometimes resulting in death.

The IMD has given the following criteria for heatwaves:

i) Heatwave is considered if maximum temperature of a station reaches at least 40°C or more for plains and at least 30°C or more for hilly regions.

ii) When normal maximum temperature of a station is less than or equal to 40°C heatwave departure from normal is 5°C to 6°C severe heatwave departure from normal is 7°C or more.

iii) When normal maximum temperature of a station is more than 40°C heatwave departure from normal is 4°C to 5°C severe heatwave departure from normal is 6°C or more.

iv) When actual maximum temperature remains 45°C or more irrespective of normal maximum temperature, heatwaves should be declared. 

• Heatwaves amplify many risks, such as health-related or economic risks, including increased human mortality, drought and water quality, wildfire and smoke, power shortages and agricultural losses.  

• The health impact of heatwaves typically involve dehydration, heat cramps, heat exhaustion and/or heat stroke.

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