New Delhi, Nov. 17 -- Delhi's most toxic fortnight of the year - the November 1 to 15 stretch that has historically produced the Capital's foulest air - has logged its lowest average air quality index (AQI) in three years. Yet the city has continued to breathe air that is overwhelmingly in the "very poor" to "severe" range. This year's average of 349 is marginally lower than 367 in 2024 and 376 in 2023, and only a shade higher than 345 in 2022.

Experts, however, cautioned that this apparent dip should not be mistaken for cleaner air.

The lower numbers, they said, stem from a combination of meteorological luck, a delayed spike in stubble burning caused by flooding in Punjab, and a Diwali that arrived before the winter inversion set in. F...