Delhi’s air quality improves to ‘moderate’, but forecasts warn of relapse soon

Forecasts by the Air Quality Early Warning System (AQEWS), however, suggest the air quality is expected to go back to very poor on Thursday.

Delhi’s air quality improved marginally on Wednesday owing to a rise in wind speed, even as forecasts indicated that the relief may be short-lived with pollution levels expected to worsen again from Thursday.

In the early hours of Wednesday, the speed was around 8-9 kmph, which further increased to about 12 Kmph by Wednesday evening. (RAJ K RAJ /HT PHOTO)

According to data from the Central Pollution Control Board (CPCB), the 24-hour average air quality index (AQI) was recorded at 202 (poor) at 4pm on Wednesday, showing a sharp improvement from 291 (poor) the previous day. By 7pm, the air quality had further improved to 197 (moderate), with the AQI logged at 221 at 10am and 215 at 11am, indicating steady improvement through the day.

Experts attributed the change to an increase in wind speed since late Tuesday night.

“The wind speed had started picking up from late Tuesday night. In the early hours of Wednesday, the speed was around 8 to 9 kmph, which further increased to about 12 kmph by Wednesday evening. This was the major reason for improvement in air quality, as higher wind speed helps in dispersal of pollutants. Wind speed is expected to remain around this range for the next couple of days,” said Mahesh Palawat, vice president of Skymet.

However, forecasts by the Air Quality Early Warning System (AQEWS) suggested that the improvement is likely to be temporary.

“The air quality is very likely to be in the very poor category from Thursday to Saturday. The outlook for the subsequent six days is that the air quality is likely to be in the very poor category,” said the AQEWS bulletin issued on Wednesday evening.

Meanwhile, the city’s minimum temperature rose by a couple of notches on Wednesday to 18.4°C, which is 3.1°C above normal, as against 16.5°C the previous day. The India Meteorological Department (IMD) has forecast that minimum temperatures are likely to drop to 12 to 14°C by the weekend.

Commenting on the temporary improvement in air quality, Delhi environment minister Manjinder Singh Sirsa said it reflected the impact of “coordinated, science-based actions being implemented on the ground.”

CPCB data shows that the 24-hour average AQI on November 5, 2025, stood at 202, compared to 373 in 2024, 454 in 2023, 381 in 2022, 462 in 2021, 450 in 2020, and 324 in 2019, suggesting a marked year-on-year improvement.

While Sirsa credited the Delhi government’s strategic approach for the better air this season, a detailed HT analysis published on November 5 raised questions about the reliability of recent pollution readings. The analysis found missing data, suspicious measurement patterns, and algorithmic loopholes in how Delhi’s average AQI is calculated, potentially leading to readings that do not accurately represent on-ground conditions.

An examination of 168 hours of CPCB monitoring data between October 28 and November 4 showed that missing station data was not random, with more gaps recorded during highly polluted hours than cleaner ones, effectively making the city’s air appear less toxic than it may have been.

Separately, Sirsa said that enforcement agencies had intensified field inspections across pollution hotspots.

“In the last 24 hours, our teams have inspected 387 construction and demolition sites, 79 municipal solid waste locations, 22 DG set installations, and 12 hotels and restaurants to check fuel usage and dust control compliance. Action has been taken wherever violations were found, and we have intensified dust mitigation and road cleaning operations across all pollution hotspots,” he said.

Sirsa added that over 500 inspections were conducted in total by teams from the Delhi Pollution Control Committee (DPCC), Municipal Corporation of Delhi (MCD), New Delhi Municipal Council (NDMC), and other agencies.