New Delhi: This April witnessed heatwave conditions in Delhi, but average temperatures remained lower than those recorded in the city last April. The mean maximum temperature stood at 37 degrees Celsius, compared to 39 degrees Celsius in April 2025, though it was still above the long-period average of 36.5 degrees Celsius.
Lower Pollution Levels
Pollution levels in April were also lower than the past two years, aided by rain and strong winds. The average air quality index (AQI) was 179.4 this April against 213 in April 2025 and 182 in April 2024.
Rainfall and Temperature Trends
Met officials stated that intermittent rain and overcast conditions during the beginning and end of the month prevented average temperatures from rising further. According to a Times of India report, this month logged 30mm of rainfall, making it the wettest April since 2008. In contrast, April 2025 recorded just 0.7mm of rainfall against the month's normal of 16.3mm.
India Meteorological Department data shows that the city experienced four rainy days between April 1 and 8 this year, when the maximum temperature mostly stayed below normal. Although temperatures began rising from April 9, the mercury crossed the 40-degree mark on April 16 for the first time this year.
The city saw nine days when the mercury exceeded 40 degrees Celsius. Of these, Delhiites endured three heatwave days between April 23 and 25. While isolated heatwaves were recorded in parts of the city on two days, a citywide heatwave was declared on April 24 when the mercury touched 42.8 degrees Celsius, making it the hottest April day in four years. Another spell of rain, along with overcast skies, was reported towards the month-end as the day temperature dipped below 40 degrees Celsius on April 28.
Night Temperatures
Night temperatures were lower than in 2025. The mean minimum temperature in April this year was 20.9 degrees Celsius, compared to 22 degrees Celsius last April. However, the minimum temperature settled at 28.4 degrees Celsius, 4.6 degrees above normal, at the base station Safdarjung on Tuesday. A warmer night was recorded nine years ago when the temperature touched 29 degrees Celsius on April 22, 2017.
The city may witness rain and gusty winds of up to 50 kmph on Wednesday night and Thursday. Safdarjung logged 1.8mm of rainfall till 8:30 am.
Air Quality Improvement
The meteorological conditions also kept air quality better. The average AQI was 179.4 till April 29 this year, but the month saw one satisfactory day and 10 poor days. This was similar to April 2023 when the average AQI was 175.5.
Dust and ozone were the main pollutants this April. Dipankar Saha, former head of the Central Pollution Control Board's air laboratory, said, 'Wind helps in dispersion of pollutants and also doesn't allow stagnation of pollutants in the atmosphere. The rate of ozone penetration also increases with clear and dust-free atmospheric conditions. The concentration of ozone is expected to be on the higher side during the day.'
