Colder days, marginally improved air in Delhi over next few days

Delhi’s air quality is expected to improve marginally with the surface wind speed picking up but it will continue to remain poor over the next few days, said government agencies.

The national Capital woke up to witness the coldest morning of the season Sunday, with the mercury dropping to 7.2 degrees Celsius — a notch below the season’s average. The city should brace for colder days ahead as minimum temperature is likely to drop to 6 degrees Celsius by the middle of the week, officials of the India Meteorological Department (IMD) said.

Moderate fog engulfed Delhi on Sunday. (Sanchit Khanna/HT PHOTO)

This was the lowest minimum temperature recorded this season. Last on December 8, the night temperature had dropped to 7.6 degrees Celsius. The season’s normal minimum temperature is around 8 degrees Celsius, officials said.

The drop in minimum temperature is attributed to the cold westerly winds and snowfall in northwest India. “Snowfall in areas such as Uttarakhand, parts of Himachal Pradesh and Jammu and Kashmir has brought cold winds to Delhi, triggering a drop in the mercury. The minimum temperature may drop to around 6 degrees Celsius on December 19,” the official said.

On Sunday, moderate fog also engulfed the city which is expected to witness shallow fog over the next two days. The IMD had earlier predicted a moderate-to-dense fog cover, which is likely to reduce the visibility to less than 50 metres. According to officials, strong winds did not let the fog become dense. As a result, the visibility recorded at the IGI airport in the morning was around 500-600 metres. On Monday, the visibility is likely to range between 500 metres and 999 metres, officials said.

“The fog has downgraded to shallow because wind speed has picked up. Shallow fog is likely to occur over the next two-three days. It may increase to moderate only around December 20, when some clouds are expected,” a senior official of the IMD’s regional weather forecasting centre (RWFC) said.

Meanwhile, Delhi’s air quality remained in the ‘poor’ category on Sunday. The air quality is expected to improve marginally with the surface wind speed picking up but it will continue to remain poor over the next few days, said government agencies.

Delhi’s AQI was recorded as 282, inching close to the ‘very poor’ category. An AQI between 100 - 200 is classified under ‘moderate’ category, 201 and 300 ‘poor’, 301 and 400 ‘very poor’ and 401 and 500 ‘severe’.

“Though wind speed has picked up, which may improve air quality marginally, other meteorological factors such as high levels of relative humidity are still unfavourable for dispersion of pollutants,” read a statement issued by Safar, the Union government’s air quality forecasting system.