The minimum temperature in the national capital on Sunday dipped to 5.5 degrees Celsius, two notches below the season's average, the India Meteorological Department (IMD) said.
The minimum temperature in the city was recorded at 10.7 and 10.2 degrees Celsius on Friday and Saturday, PTI reported.
Visibility in Ambala, Dehradun, Bareilly, and Varanasi was recorded at 25 metres at 5:30 am. While in Chandigarh, Patiala, Baharaich, Gaya, Purnea, Kailashahar, and Agartala, it was recorded at 50 metres, officials said.
According to the IMD, 'very dense' fog is when visibility is between 0 and 50 metres, 51 and 200 metres is 'dense', 201 and 500 metres 'moderate', and 501 and 1,000 metres 'shallow'.
The weatherman predicted a mainly clear sky on Sunday, with the maximum temperature likely to settle around 19 degrees Celsius.
The humidity in the national capital was recorded at 97 per cent at 8.30 am, they said.