In a rare turn for the capital, Delhi has clocked its cleanest stretch of air in eight years (excluding the COVID year), as per data from CPCB and CAQM. Between January and September 2025, the city’s average AQI stood at 164, down from 178 in 2024 and 167 in 2023. The monsoon months were particularly gentle: July–September averaged an AQI of 91, the best monsoon air quality since 2018 (excluding 2020).

Officials attribute the improvement to a mix of favourable meteorological conditions less heat wave trapping, regular rainfall cleaning the air and ongoing regulatory efforts under the Graded Response Action Plan and CAQM interventions. So far in 2025, Delhi has not witnessed any “severe” or “severe-plus” air days (those categories featured in past years).

Still, the progress is fragile. As the colder months approach, risks loom: crop-burning in neighbouring states, festivity-driven emissions, and cooler weather that can trap pollutants near the ground. Experts caution that sustaining gains will depend on stricter source control, better regional coordination, and consistent enforcement even when skies turn clear.