Delhi's AQI has moderated to 534 levels much lower than the levels seen a day ago, according to Safar India.
As per the US Embassy data, at 2 p.m. the AQI as per PM 2.5 was 361, much lower than the 500 plus levels seen on Sunday and earlier on Monday.
According to Safar India, a significant improvement was expected by Monday afternoon as very high boundary layer wind speed of 26 kmph was also observed early morning.
High surface and boundary layer wind are also expected for Tuesday which will further improve air quality to "very poor" level.
A fresh Western Disturbance is approaching north India and scattered rainfall and change in wind direction is expected by November 8 in Delhi region likely to positively influence AQI, the Met report said.
It said the light drizzling in calm wind conditions acted as a catalyst towards increasing air-holding capacity, triggering secondary particle formation (SPF-a mechanism when PM2.5 starts to multiply rapidly).
In cloudy days like Sunday, in the absence of sufficient solar radiation, the mixed layer continued to be very low even during the daytime, arresting pollutants firmly.
It is a unique condition because such a process is characteristic of the colder foggy period of December-January, the Safar forecast said.
Stubble burning on Sunday had the highest share in terms of the absolute number of PM2.5 of 120. This along with secondary particulate formation due to drizzled calm winds notched the seasons' high PM2.5 levels to "severe plus".
( With inputs from IANS )