The national capital on Friday recorded a minimum temperature of 7.1 degrees Celsius, slightly below the seasonal average,the weather department said.
Dense fog prevailed in parts of the city, with the Palam Observatory near the Indira Gandhi International Airport noting a visibility level of 50 meters at 5:30 am.
Officials said several flights departing from the Indira Gandhi International (IGI) airport were delayed.
Indian Railways reported delays of one to six hours for 22 Delhi-bound trains due to foggy conditions.
Visibility categories: Very dense fog (0-50m), dense fog (51-200m), moderate fog (201-500m), and shallow fog (501-1,000m).
The Central Pollution Control Board (CPCB) recorded an overall Air Quality Index (AQI) of 347 at 9 am.
AQI categories: Good (0-50), Satisfactory (51-100), Moderate (101-200), Poor (201-300), Very Poor (301-400), Severe (401-500).
Relative humidity at 8:30 am was 95%, according to the IMD bulletin.
The weather department forecasts a clear sky with very dense fog for Friday, and the maximum temperature is expected to reach around 19 degrees Celsius. (With inputs from PTI)
