Shallow fog plunges visibility as air quality in Delhi remains very poor

A 24-hour average Air Quality Index (AQI) of 309 (very poor) was recorded at 7am on Tuesday compared to 310 (very poor) at 4pm a day earlier

Shallow fog in Delhi in the early hours of Tuesday plunged the visibility to 750 metres in Palam at 7:30am even as the air quality remained in the lower end of the very poor category with the minimum temperature rising five degrees above normal to 14.6°C on Monday compared to 10°C a day earlier. Low temperatures lead to stagnation in the atmosphere slowing down the dispersion of pollutants. A rise in the mercury has the opposite impact.

IMD on Sunday said a warmer winter was expected. (HT PHOTO)

A 24-hour average Air Quality Index (AQI) of 309 (very poor) was recorded at 7am on Tuesday compared to 310 (very poor) at 4pm a day earlier. Delhi last recorded a severe air day on November 24, when the AQI was 415

The India Meteorological Department (IMD) said the minimum temperature was expected to remain over 10°C this week. Cloudiness expected in northwest India due to Cyclone Michaung, which was expected to make landfall in Andhra Pradesh on Tuesday, was likely to bring moisture to northern India.

Kuldeep Srivastava, an IMD scientist, said the cloudiness means that the mercury is unlikely to dip much over the next few days.

IMD on Sunday said a warmer winter was expected in the country from December to February. It added intensity and the frequency of cold waves will be lower than normal in most parts of north, northwest, central, east, and north-east India.