Delhi’s air quality continued to improve but remained in the ‘poor’ category on Saturday, a day after light showers, accompanied with strong winds enabled to bring down the pollution levels.
Delhi’s 24-hour average air quality index (AQI) was recorded at 213 (poor) at 7am on Saturday — an improvement from Delhi’s reading of 279 (poor) at 4pm on Friday.
Strong winds are expected to persist in the national Capital on Saturday, possibly touching 18 km/hr, which is likely to help the AQI improve further, officials said. Though a slight drop in wind is expected on Diwali day (Sunday), it should still be around 8-10 km/hr, they added.
“We saw the impact of the western disturbance, which is influencing northwest India, on Friday. This is what led to this rain spell and from Saturday onwards, moisture in the air will reduce and the air will become colder and drier,” said Kuldeep Srivastava, scientist at IMD, stating though the wind direction will switch to northwesterly on Saturday – from the predominantly southeasterly winds seen on Friday, dispersal of pollutants will continue.
“Winds may go up to 18 km/hr during the day. This wind speed will then begin to dip on Diwali day, but should still be around 8-10 km/hr,” he said.
On Friday, the Central Pollution Control Board’s (CBCP) hourly PM 2.5 concentration data showed it had improved to as low as 37 micrograms per cubic metre at 6am — a reading that is well within the national standard of 60 micrograms per cubic metre.
In comparison, the same PM 2.5 levels peaked at 488 micrograms per cubic metre at 12pm on November 5, which was the fourth consecutive day when Delhi’s air was in ‘severe’ category.
Friday’s downpour also saw Delhi’s maximum temperature dropping, with it recorded at just 22.7°C — seven notches below normal and Delhi’s lowest maximum for November since it was 22°C on November 29, 2019.
Though a gradual rise is expected in the coming days, the maximum should remain below 30°C in the next seven days now, the India Meteorological Department (IMD) has said.
Delhi’s minimum was meanwhile recorded at 16.2°C on Friday morning — two above normal.
With fresh snowfall recorded in the higher reaches and northwesterly winds returning from Saturday, the IMD forecasts a dip in minimum temperature — to 13°C by Monday. It should hover around 14°C over the weekend, including today. The maximum is meanwhile forecast to rise to around 27°C today and around 28°C on Sunday.
Real-time data showed the visibility at Palam stood at 800 metres at 7am. This is expected to go over 1500 metres during the day, as strong winds help improve clarity further, officials said.