Delhi’s air quality deteriorates as mercury plunges to lowest this season

Delhi’s air quality deteriorated on Friday but remained in the poor category even as the mercury plunged to the lowest this season to 15.2°C, which is two degrees below normal. The previous lowest of 15.6°C was recorded on October 22 when Delhi recorded its only very poor air day so far. An increase in wind speed the next day brought air quality index (AQI) back to the poor category and it has remained so since.

An average air quality index (AQI) of 258 was recorded at 10.05am compared to 256 on Thursday. The air quality was expected to deteriorate further over the weekend and return to the very poor category.

“Delhi’s air quality...is likely to be very poor on Saturday and Sunday. The outlook for the subsequent six days shows the air quality is likely to remain in between very poor and poor,” said a bulletin of the Union earth sciences ministry’s Early Warning System.

AQI between 0-50 is considered good, between 51 and 100 as satisfactory, between 101 and 200 as moderate, between 201 and 300 as poor, between 301 and 400 as very poor, and over 400 as severe.

The minimum temperatures were likely to hover around the 16°C mark until October 30 while the maximum between 31 and 33°C.