New Delhi: The air quality in the national capital remained in the severe category on Saturday and a slight improvement is likely in the next 24 hours, officials said.
The overall air quality index of the city stood at 418, which falls in the severe category, at 4 pm.
Foggy conditions and a cloud cover prevented sunlight from heating the ground. The cold air trapped pollutants, the officials said.
The city recorded a low of 9.5 degrees Celsius and a high of 18 degrees Celsius, which was three notches below the normal.
The government's air quality monitoring and forecasting service, SAFAR, said "huge" accumulation of pollutants occurred last night.
Wind speed is forecast to increase further on Sunday and the AQI is likely to improve slightly.
A decrease in the minimum temperature is also predicted and conditions are going to be highly favourable for the formation of dense fog in the next two days, it said.