The fog resulted in reduced visibility in the region.
As the mercury levels recorded a drop in Delhi and the NCR region, a thick layer of fog engulfed the national capital on Monday.
The fog resulted in reduced visibility in the region and the vehicles were seen with their headlight on during the morning hours.
The air quality was in the 'very poor' category with an overall AQI of 327 in Delhi today.
The AQI in Noida was recorded at 399 while AQI in Gurugram stood at 302.
The Air Quality Index from 0 to 100 is considered as good, while from 100 to 200 it is moderate, from 200 to 300 it is poor, and from 300 to 400 it is said to be very poor and from 400 to 500 or above it is considered as severe.
According to the System of Air Quality and Weather Forecasting and Research (SAFAR), Delhi's air quality was also recorded in the 'very poor' category on Sunday.
Smog engulfed the national capital as the air quality remained in the 'very poor' category with an overall Air Quality Index of 327 on Sunday evening.
The AQI in the Delhi University area stood at 365 while the AQI was recorded to be at 293 near Lodhi Road. The area nearby the IIT Delhi recorded an AQI of 297 while it stood at 335 at the IGI Airport T3.
Delhi air stood at 'very poor' category on Sunday morning with AQI reaching 322. The Air Quality of the national capital, which was at a moderate level for the last few days, dipped over the weekend.