The 24-hour average AQI reached 373 (‘very poor’) at 8 a.m. on Monday, slightly down from 382 at 4 p.m. on Sunday, which marked the highest level this winter season, surpassing the 364 (‘very poor’) recorded on October 23.
Eleven of Delhi’s 40 air quality monitoring stations recorded “severe” pollution levels as haze settled over the city, following a weekend drop in wind speeds that slowed pollutant dispersion. Visibility at Palam was 2,000 meters around 3:30 a.m., dropping to approximately 1,300 meters by 8 a.m.
As of 8 a.m., data from the Central Pollution Control Board (CPCB) showed Anand Vihar with an Air Quality Index (AQI) of 434 and Vivek Vihar at 424, both in the “severe” category. The 24-hour average AQI was 373 (“very poor”) on Monday morning, down from 382 at 4 p.m. on Sunday, marking the season’s highest so far and surpassing the 364 recorded on October 23. The year’s worst AQI was 392 (“very poor”) on January 31. Delhi’s AQI is expected to remain in the “very poor” zone until Wednesday, as meteorological conditions are likely to remain highly unfavorable for pollutant dispersion.
The CPCB categorizes the Air Quality Index (AQI) as follows: 0-50 is considered “good,” 51-100 is “satisfactory,” 101-200 is “moderate,” 201-300 is “poor,” 301-400 is “very poor,” and any level above 400 is classified as “severe.”
The wind direction has shifted from north-westerly to south-easterly, resulting in relatively calm conditions. Temperatures have also begun to drop after a warm October.
Mahesh Palawat, vice president of private forecaster Skymet Weather, indicated on Sunday that a rise in pollution levels was anticipated due to these changes in wind direction and calm winds. He noted that winds were expected to remain south-easterly by Monday, with speeds likely to be calm overnight and below 10 km per hour during the day until Tuesday. A slight increase in wind speeds is expected starting Wednesday.
On Sunday, the Commission for Air Quality Management (CAQM) announced that it was actively monitoring air quality in the region. Stage 2 of the Graded Response Action Plan (GRAP) is currently in effect in the Delhi-National Capital Region (NCR) to address pollution. Stage 3 may be implemented if the AQI reaches “severe” levels or is projected to do so. A CAQM official stated, “No meeting regarding GRAP was held on Sunday, but officials are closely tracking the AQI.”
The “severe” category prohibits all construction and demolition activities in the NCR, with the exception of emergency or essential projects. It also restricts the operations of industries not using cleaner fuels to a maximum of five days per week, mandates the shutdown of brick kilns, and bans mining and related activities.
Strong winds of 10-15 km per hour, even at night, were positively influencing Delhi’s AQI until Saturday, helping to disperse a significant amount of firecracker emissions from Thursday and Friday.
On Diwali day, the AQI in Delhi was recorded at 328 (“very poor”). It increased slightly to 339 (“very poor”) the following day at 4 p.m. This marked the second-lowest AQI on the day after Diwali in the past nine years.
