Capital records cleanest October air in over a decade, wettest in four years

As winter sets in and the capital enters its peak pollution season, this month has set several records for weather and air quality. Delhi has recorded its cleanest October air in more than a decade, its wettest October in four years and its coldest October day since 2011.

Delhi recorded an average Air Quality Index (AQI) of 167 this October, the lowest for the month since 2015, according to an analysis by the Centre for Research on Energy and Clean Air (CREA).

The city also recorded its wettest October in four years, with cumulative rainfall of 123.3 mm till 8.30 am on October 30 -- the fourth-highest since 1954. The last time Delhi received higher rainfall in October was in 2022, when it recorded 128 mm.

The monthly normal rainfall for the city is 15.1 mm.

The average minimum and maximum temperatures for October settled at 20.7 degrees Celsius and 32.6 degrees Celsius, respectively.

The maximum temperature on October 30 was 20.7 degrees Celsius, the coldest daily maximum recorded in October at the Safdarjung observatory since 1951, according to the data.

The AQI stood at 60 on Friday, making it the cleanest October day since October 10, 2022, when the AQI was recorded at 44. The highest AQI recorded this October was 245, the lowest monthly peak since 2015.

The average AQI in October was 167 in 2026, 223 in 2025, 234 in 2024, 219 in 2023, 210 in 2022 and 264 in 2015.

Delhi’s average AQI between January and October stood at 168, the lowest for this period since 2020, when it was 156. The analysis covers available data since 2015.

India launched its National Air Quality Index in September 2014, so comparable data for the period before its launch is unavailable, experts said.

The city recorded five days of ‘poor’ air quality, three ‘satisfactory’ days and 22 ‘moderate’ days in October so far. Air quality entered the ‘poor’ category on October 21, when the AQI rose to 245.

Since 2015, this is the first time Delhi’s air quality entered the ‘poor’ category in the second half of October. In previous years, the city’s AQI entered the ‘poor’ category during the first half of the month.

Pointing out meteorological influences on air quality parameters, Manoj Kumar from CREA said, “Delhi recorded a relatively lower average AQI in October 2026 compared with previous Octobers, although it remained 1.5 times higher than the average AQI for September 2026.

Delhi recorded 61.4 mm rainfall in the 24 hours ending 8.30 am Friday, making it the wettest October day in four years, and the sixth wettest October day since 1951. The last time the city recorded higher daily rainfall in October was on October 9, 2022, when it logged 74 mm of rain.

Among individual weather stations, Safdarjung recorded 123.3 mm of rainfall against its monthly normal of 15.1 mm, a departure of 108.2 mm or around 717 per cent above normal. Palam received 85.7 mm against its normal of 12.7 mm, recording 73 mm or around 575 per cent more rainfall than normal.

Lodhi Road recorded 130.6 mm of rainfall against its normal of 15.1 mm, a departure of 115.5 mm or around 765 per cent. The Ridge received 126.7 mm against its normal of 11.8 mm, recording 114.9 mm or around 974 per cent excess rainfall.

Ayanagar recorded 104 mm rainfall against its normal of 13.8 mm, a departure of 90.2 mm or around 654 per cent above normal.