Delhi's AQI improves after 3 days, to jump back to ‘severe’

The India Meteorological Department’s (IMD) forecast shows that the air quality in Delhi will be back to “severe” on Sunday.

The Capital woke up to a relatively improved air on Saturday after a streak of four “severe” air days, however, forecasts suggest the respite is short-lived.

Delhi’s average AQI was recorded at 370 on Saturday. (RAJ K RAJ /HT PHOTO)

The 24-hour average air quality index (AQI) on Saturday was recorded at 370 (very poor) at 4pm, according to the Central Pollution Control Board’s (CPCB) daily national bulletin. The AQI was 429 (severe) on Friday and 451 (severe plus) on Thursday. The AQI had been deteriorating consistently since last Sunday due to a drop in wind speed, making it the worst since December 2021.

The India Meteorological Department’s (IMD) forecast shows the air quality will be back to “severe” on Sunday.

According to the Air Quality Early Warning System (AQEWS) for Delhi, the predominant surface wind on Saturday was mostly from the northwest direction. The wind speed had gone to 8kmph momentarily during the day, facilitating the improvement in air quality. However, the AQEWS bulletin said that the wind speed is expected to become less than 4kmph during the night.

“The air quality is likely to be in severe category on Sunday and in very poor category from Monday to Tuesday. Meteorological condition is likely to be unfavourable for effective dispersion of pollutants. The outlook for subsequent six days is that the air quality is likely to be in very poor to poor category,” the AQEWS bulletin on Saturday evening said.

Further, IMD has also predicted two western disturbances to affect the region in the coming days. Delhi’s temperature did not show a significant change on Saturday. The minimum was logged at 7.6 degrees Celsius (°C) half a notch below normal and 0.1 °C up from Friday’s minimum. The maximum was recorded at 23.4 °C, one degree above normal and 0.1 °C above the maximum a day before.

“A western disturbance is likely to affect Delhi on December 22-23, but this will be for a short span and its effects will be momentary. However, an active western disturbance will hit the region from December 26-27, which is likely to cause scattered to widespread rainfall over the plains of northwest India and snowfall over the western Himalayan region,” Krishna Mishra, scientist at IMD said.

Experts added that the rain during the second western disturbance might cause an improvement in pollution levels.

According to forecasts by IMD, the maximum and minimum are expected to be around 24 °C and 8 °C, respectively, on Sunday. IMD has also forecast very light rain or a drizzle on Sunday and has issued a yellow alert for Monday, warning about the possibility of a dense fog.