Delhi breathes easier as sunshine and winds clear the smog — for now

However, forecasters warned that the relief may be short-lived, with conditions expected to turn unfavourable again on Saturday, likely pushing the AQI back to the ‘very poor’ range

Delhi’s air quality saw a remarkable improvement on Friday as sunny skies and brisk winds helped disperse pollutants, weather scientists said.

Visitors to Kartavya Path wear masks amid a dense layer of smog early Friday. The conditions improved as the day progressed. (RAJ K RAJ /HT PHOTO)

The Capital’s 24-hour average air quality index (AQI) improved by over 150 points — from a season-high 373 (very poor) at 4pm on Thursday to 218 (poor) at the same time on Friday. By 8pm, it further dropped to 203 (poor), according to Central Pollution Control Board (CPCB) data.

However, forecasters warned that the relief may be short-lived, with conditions expected to turn unfavourable again on Saturday, likely pushing the AQI back to the ‘very poor’ range.

Experts said that, unlike Thursday when calm winds and cloud cover trapped pollutants, Friday saw marginally stronger winds and bright sunshine, aiding both vertical and horizontal dispersion. Rain in neighbouring Haryana and Uttar Pradesh may also have had a “washout” effect on pollutants in the NCR.

“Winds only began to pick up from Friday morning. What is likely to have helped the AQI is rain in Faridabad and even in pockets of Uttar Pradesh near Noida. Even parts of Delhi recorded trace rainfall on Thursday, which was all down to increased moisture coming from Cyclone Montha,” said Mahesh Palawat, vice president at Skymet.

The Centre’s Air Quality Early Warning System (EWS) had earlier predicted ‘very poor’ air for Friday. Its latest forecast warns of continued poor conditions. “Delhi’s air quality is very likely to be in the ‘very poor’ category from November 1 till November 3. The outlook for the subsequent six days shows AQI is likely to be in the ‘very poor’ category,” the EWS said in its daily bulletin.

According to the CPCB, an AQI of 51–100 is “satisfactory”, 101–200 is “moderate”, 201–300 is “poor”, 301–400 is “very poor”, and above 400 is “severe”.

Delhi’s environment minister Manjinder Singh Sirsa held a review meeting on Friday to assess air pollution measures at the city’s 13 hotspots and other locations. He credited the day’s improved air to “sustained action on ground, aided by meteorology”.

“Our entire government machinery — MCD, DDA, NDMC, DSIDC, and others — has been working in full coordination,” Sirsa said.

“As a result, Delhi’s AQI is 218 today, compared to 357 on the same day last year. Over 1,200 personnel were deployed across 443 teams to curb open waste burning, 1,000 across 378 teams for dust control, and 1,500 across 578 teams for vehicular pollution checks. Mechanised road sweepers and anti-smog guns were also pressed into service,” he added.

Meanwhile, the Commission for Air Quality Management (CAQM) said the period between January and October this year recorded the cleanest air in eight years, excluding 2020 — the lockdown year.

Delhi’s average AQI for this period was 170, compared to 184 in 2024, 172 in 2023, 187 in 2022, 179 in 2021, 156 in 2020, 192 in 2019, and 201 in 2018, the CAQM said, adding that it continues to work with all agencies to curb pollution in the region.