Delhi’s air quality again deteriorated from poor to very poor category on Friday as the day progressed.

The overall Air Quality Index (AQI) soared from 273 in the morning and stood at 309 in the noon, as per the System of Air Quality and Weather Forecasting And Research (SAFAR).

According to Central Pollution Control Board data, the AQI was at 325 in Anand Vihar, 328 in Ashok Vihar, 315 in Old Delhi’s popular marketplace Chandni Chowk, 335 in Dwarka Sector 8 and 302 in RK Puram, all falling under the ‘very poor’ category.

Other places such as Mathura Road, Indira Gandhi International Airport (Terminal 3), Dilshad Garden, Lodhi Road and Delhi University (North Campus) recorded ‘poor’ air, with the AQI values clocking at 235, 259, 267, 205 and 219, respectively.

Officials from Ministry of Earth Sciences stated that Delhi’s overall AQI is expected to marginally improve on Saturday and Sunday as a result of “relatively better ventilation conditions” due to accelerated local surface winds. However, they also forecast the air quality to deteriorate on November 23.

The ministry also estimated the stubble burning fire share in city’s air at 15 per cent as the stubble burning incidents reduced marginally from previous day and its count estimated to be around 495.

“Energetic surface winds are forecast for the next two days and likely to influence AQI positively. The AQI is likely to marginally improve and be in the Very Poor to Poor category for the next two days.

“AQI is forecast to marginally deteriorate and be in the Very poor category on 23rd November,” they added.

An AQI reading between 0 and 50 is considered “good”, 51 and 100 “satisfactory”, 101 and 200 “moderate”, 201 and 300 “poor”, 301 and 400 “very poor”, and 401 and 500 “severe”.