India, Oct. 29 -- A shallow haze enveloped Delhi in the early hours of Wednesday as the air quality was in the "poor" category and the mercury dipped further and settled at 18.2degC compared to 20degC a day earlier.

Data from the Central Pollution Control Board showed the AQI was 272 (poor) at 10am on Wednesday. The 24-hour average AQI was 292 at 4pm on Tuesday. The Air Quality Early Warning System (AQEWS) for Delhi said the air quality was expected to remain in "poor" zone this week.

The India Meteorological department (IMD) said cloudy skies were expected throughout the day on Wednesday. "A mist formation might be seen in the late afternoon to evening hours on Wednesday," said an IMD official.

The mercury was expected to go up to 29d...