The air quality in the national capital was recorded in the 'very poor' category on Friday morning while the minimum temperature was 12.5 degrees Celsius, three notches above the season's average.
At 9 am on Friday, the air quality index (AQI) was 358, the Central Pollution Control Board (CPCB) data showed.
Neighbouring NCR towns Faridabad (289) and Greater Noida (250) recorded 'poor' air quality on Friday morning. The AQIs in Ghaziabad (331), Gurgaon (309) and Noida (315) were in the 'very poor' category.
Delhi's 24-hour AQI was 429 on Thursday.
An AQI between zero 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'.
The minimum temperature of the national capital was recorded at 12.5 degrees Celsius, three notches above the season's average, India Meteorological Department (IMD) said.
While the maximum temperature is likely to settle at 22 degrees Celsius, the relative humidity at 8.30 am was 91 per cent.
Delhi recorded the lowest maximum temperature of the season so far on Thursday as it plummeted five notches below normal and settled at 19.8 degrees Celsius. The city also witnessed light rains on Thursday
The weather department has predicted "shallow fog" for Delhi on Friday.