India, Jan. 7 -- The air quality in the city deteriorated on Tuesday and entered the "very poor" category after a day of slight improvement. The India Meteorological Department (IMD) has issued a yellow alert for cold wave in the city until Thursday.

The 24-hour average air quality index (AQI) on Tuesday was logged at 303, up from 240 on Monday and down from 333 on Sunday, according to the Central Pollution Control Board (CPCB). The city was shrouded in thick haze on Tuesday, reducing the visibility to below 100 metres on several stretches during the early hours, such as Golf Course Road, Delhi-Jaipur and Dwarka expressways.

The restricted visibility observed at 6.30am began to improve slightly above 250 metres at 11am. With the yellow ...