The share of stubble burning in Delhi's pollution dropped to a meagre 3 per cent on Wednesday due to a change in the wind direction, according to the government's air quality monitoring and forecasting service SAFAR.
Punjab had on Tuesday recorded the season's highest farm fire count of 6,668 despite a recent Supreme Court order to completely halt stubble burning.
SAFAR said, "A change in the wind direction has led to a very low biomass plume intrusion in spite of the fact that the fire count observed yesterday was very high."
It said Delhi's overall air quality index improved significantly (from very poor to poor) on Wednesday, more rapidly than predicted.
"An approaching western disturbance brought cleaner air to the region. Isolated thundershower is expected for the next two days and the wind direction is likely to be southeasterly on November 7. So, no biomass intrusion," it said.
SAFAR's data showed the share of stubble burning in Delhi's PM2.5 pollution was just 3 per cent on Wednesday and is likely to be 2 per cent on Thursday.
The air quality monitor said AQI was expected to enter the moderate category in case of high rainfall on Thursday.
However, by November 8 evening, the wind direction is expected to change to northwesterly and the air quality is likely to enter the "very poor" category again, it said.