Delhi's August marked by excess rainfall, heat, and poor air quality

The national capital recorded 653.9 mm of rainfall at the Safdarjung weather station since the onset of the monsoon season, significantly exceeding the long-period average of 506.7 mm, the India Meteorological Department said. The surplus of 147.2 mm represents a 29 percent increase over normal seasonal precipitation.

Delhi registered its wettest opening week of August in 15 years, with 127 mm of rainfall recorded during the first seven days of the month. This marked the highest rainfall for the period since 2011. The month also witnessed an intense rainfall episode on August 25, when Safdarjung recorded 99.1 mm of precipitation in 24 hours—the highest single-day August rainfall in two years.

Beyond excess precipitation, the capital grappled with persistently warm night-time temperatures throughout August, creating conditions that prevented typical monsoon cooling. These warmer nights contributed to rising humidity levels across the city.

The combination of moisture and atmospheric conditions during August resulted in an average air quality index that reached three-year highs, indicating deteriorating air quality despite the increased rainfall. Meteorologists noted that while monsoon rains typically help disperse pollutants, the stagnant warm air masses and humidity levels limited their dispersal effect during the month.