Patna : The India Meteorological Department (IMD) has warned that 2025 is likely to be the hottest year on record, with the number of heatwave days expected to double in several northwestern states. The department’s projections indicate that states such as Haryana, Punjab, Rajasthan, Himachal Pradesh, Jammu and Kashmir, Uttarakhand, and Delhi could witness heatwaves lasting 10 to 12 days, compared to the usual 5 to 6 days recorded between April and June.
Record Heat in 2024
IMD data reveals that 2024 was among India’s hottest years, with heatwave conditions affecting the country for a cumulative 554 days. It is important to note that this figure does not denote 554 consecutive calendar days of heatwaves. Instead, the number represents the total heatwave occurrences across various states throughout the year. For example, if Delhi experiences a 10-day heatwave, Rajasthan 15 days, Uttar Pradesh 12 days, and Bihar 8 days in a given month, the total heatwave count would be 45 days.
Doubling of Heatwave Days Expected
With the projected increase in heatwave duration, meteorologists warn that 2025 could set new temperature records. A senior IMD scientist claimed that if heatwave days double this year, the country could face extreme temperatures, with mercury levels soaring 5°C or more above normal for extended periods.
Rising Temperatures Across States
Currently, temperatures in eight states, including Maharashtra, Uttar Pradesh, Chhattisgarh, Telangana, and Madhya Pradesh, have already crossed the 40°C mark, a worrying sign as early as March. Delhi recorded 40.1°C, while Prayagraj in Uttar Pradesh saw temperatures soar to 41.5°C. Similar conditions were reported in Akola, Nizamabad, and Rajnandgaon.
Factors Driving Intense Heat
The IMD attributes the rising heat to two major factors:
- El Niño Conditions: Abnormally warm waters in the Pacific Ocean, characteristic of El Niño, result in reduced rainfall and exacerbate heat conditions in India. The impact of El Niño is expected to persist until June 2025.
- Climate Change: Long-term changes in climate patterns are increasing the frequency, duration, and intensity of heatwaves.
Heatwave Criteria and Severity
Heatwaves are classified based on temperature deviations from normal. For plains, a heatwave is declared when temperatures exceed 40°C, while for coastal areas, the threshold is 37°C. In hilly regions, a heatwave is recorded when the maximum temperature crosses 30°C. A temperature increase of 6.5°C or more above normal qualifies as a severe heatwave.
A Decade of Rising Heat
IMD data for the last decade shows a sharp rise in the number of heatwave days:
- 2024: 554 days
- 2023: 230 days
- 2022: 202 days
- 2019: 174 days
- 2018: 90 days
