HEAT WAVES IN INDIA

A Heat Wave is a period of abnormally high temperatures, more than the normal maximum temperature that occurs during the summer season, mostly in the NorthWestern parts of India.

Heat Waves 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 living in these regions as they cause physiological stress, sometimes resulting in death.

The Indian Meteorological Department (IMD) has given the following criterion for Heat Waves:

• Heat Wave need not be considered till maximum temperature of a station reaches atleast 40°C for Plains and atleast 30°C for Hilly regions .

• When normal maximum temperature of a station is less than or equal to 40°C Heat Wave Departure from normal is 5°C to 6°C Severe Heat Wave Departure from normal is 7°C or more.

It has been an observable trend that the summers are getting hotter and hotter, every year, in India. It has become severe this year and several places in India have crossed the 50-degree Celsius mark this year.

Since May 2024, a severe heat wave affected India. The heat wave occurred during the Indian dry season, which typically lasts from March to July with peak temperatures in April and May. Temperatures in the capital Delhi alone exceeded nearly 53 °C. It was considered the country's hottest summer in 120 years.

• When normal maximum temperature of a station is more than 40°C Heat Wave Departure from normal is 4°C to 5°C Severe Heat Wave Departure from normal is 6°C or more.