The official index reached 370 at 9 a.m. and several districts exceeded 400, or severe. Fireworks worsened pollution already produced by traffic, dust, construction, crop burning and stagnant winter air; they do not explain the whole crisis.
A private platform recorded an instantaneous AQI peak of 512, while the previous day's official average was 261. The measures differ, but fine particles remain hazardous and forecasts point to several adverse days.
Rain and thunderstorms on September 26 triggered a yellow alert in several districts. The daily AQI was 72, in the satisfactory category, while the monsoon season closed at 728.6 mm, 16% above average.