Delhi on Thursday continued to grapple with rising pollution as the air quality index (AQI) settled in the 'very poor' category in most areas of the city.

The average AQI recorded in the national Capital was at 306 in the ‘very poor’ category at 4 pm with 18 areas of the city crossing the 300 mark according to the Central Pollution Control Board (CPCB). At 7 pm, the CPCB revealed that Anand Vihar recording an aqi of 366, NSIT Dwarka recording 345, Jahangirpuri recording 338, Bawana recording 331, Vivek Vihar recording 327, Rohini recording 326, Sonia Vihar recording 323, Burari crossing recording 323, Mandir Marg recording 312, Alipur recording 311, Mundka recording 310, Ashok Vihar recording 310, Dwarka sector 8 recording 307, Najafgarh recording 307, Major Dhyan Chand National Stadium recording 306, Wazirpur recording 305, Nehru Nagar recording 304 and Patparganj recording 301.

The AQI was recorded at 328 at 9 am with a thick layer of smog shrouding the city in the morning hours, according to the Central Pollution Control Board (CPCB).

During the winter months, Delhi experiences severe pollution, driven by a combination of factors such as low wind speeds, dropping temperatures, high moisture levels and the presence of pollution particles that act as surfaces for condensation.

According to the Air Quality Early Waring System for Delhi, the air quality is likely to be in ‘poor’ category on Friday and ‘very poor’ category from Saturday to Sunday. “The outlook for subsequent 6 Days: The air quality is likely to be in Very Poor to Severe category,” it said.

Furthermore, it said that the relatively low wind speeds is also not helping in reducing the high aqi in Delhi. “Meteorological conditions are unfavourable for effective dispersion of pollutants as calm winds prevail during night,” it said.

However, the average AQI has seen a dip in that of Wednesday even as the city recorded 364 aqi a day before according to the CPCB.

The deteriorating air quality in the national capital has triggered a 30 to 40 per cent surge in respiratory issues, with children and the elderly the worst hit. Anti-pollution restrictions under the Graded Response Action Plan (GRAP)-II came into force on Tuesday.

Meanwhile, the minimum temperature in the city was recorded at 20.7 degrees Celsius, three notches above the season's normal, according to the India Meteorological Department (IMD).