Delhi AQI Remains Very Poor, Similar Conditions Likely Till December 19

Delhi's air quality showed marginal improvement on December 17, 2025, with the 24-hour average Air Quality Index (AQI) recorded at 328 by early morning, remaining firmly in the 'very poor' category after dipping from 354 the previous afternoon. Strong surface winds reaching up to 20 km/hr on Tuesday aided pollutant dispersion, ending a three-day streak of 'severe' air that peaked at 461 on Sunday—marking the season's worst day and the second-highest December AQI since records began in 2015.

The India Meteorological Department reported persistent shallow fog, with visibility at 900 metres at Safdarjung and 1,100 metres at Palam, alongside consistent early-hour winds of 7-10 km/hr. These conditions allowed smoother operations at Indira Gandhi International Airport following recent disruptions. Similar wind speeds of 15-20 km/hr were anticipated briefly on Wednesday, with northwesterly winds expected to continue through Friday.

According to the Centre's Air Quality Early Warning System, Delhi's AQI is forecast to stay in the 'very poor' range from December 17 to 19, with potential slippage into 'very poor' to 'severe' thereafter. Of the city's 39 monitoring stations, 30 registered 'very poor' readings at 8 a.m., with the remainder in 'poor', a notable shift from Tuesday's single 'severe' station and Monday's 28.

Also Read: Bengaluru Records 14.5°C as Cold Spell Persists, IMD Predicts Similar Conditions

Meteorologist Mahesh Palawat from Skymet noted that sustained winds until Friday would provide limited relief, preventing further escalation. The Central Pollution Control Board classifies AQI 301-400 as 'very poor', where prolonged exposure can cause respiratory illness, particularly affecting sensitive groups.

Winter stagnation, low mixing heights, and trapped emissions from vehicles, industry, and regional sources continue to drive pollution levels. Authorities maintain strict Graded Response Action Plan measures, including restrictions on older vehicles and construction, amid calls for enhanced enforcement.

Also Read: Delhi’s AQI Nears Severe Category Amid Sharp Drop in Wind Speed