These winds are likely to continue on Tuesday, leading to further improvement in the air quality to the 'poor' category (if no increase in fire count), it said.
Strong surface winds barrelled through Delhi and neighbouring areas on Monday, improving the air quality.
The city recorded its 24-hour average air quality index at 311, down from 349 on Sunday. It was 374 on Saturday. Neighbouring Faridabad (330), Ghaziabad (254), Greater Noida (202), Gurgaon (310) and Noida (270) also recorded a slight improvement in the air quality.
R K Jenamani, a senior scientist at the India Meteorological Department (IMD), said westerly winds gusting up to 25 kmph improved visibility to 3,200 metres.
So far, Monday has been the only day in November when the Palam Observatory reported “visibility of more than 3000 m and such strong winds”, he said.
The Ministry of Earth Sciences air quality monitor SAFAR said the AQI was recorded in the lower end of the “very poor” category on Monday, a “significant” improvement from the day before due to the low fire count and strong transport-level winds blowing from northwest direction dispersing pollutants.
These winds are likely to continue on Tuesday, leading to further improvement in the air quality to the ‘poor’ category (if no increase in fire count), it said.
Local surface wind speed is also relatively high on Monday and will remain so on Tuesday, it said, adding local and transport-level winds are likely to slow down from Wednesday and result in slight deterioration in the air quality.
SAFAR said 909 farm fires accounted for six per cent of Delhi’s PM2.5 pollution on Monday.