As the national capital remained blanketed under dense fog, around 30 flights departing from Indira Gandhi International airport were delayed and 17 were cancelled due to weather conditions.
The authorities said that low visibility procedures were in progress at the Delhi airport.
Many passengers were seen waiting at the airport with their luggage.
Meanwhile, 30 trains to Delhi from various parts of the country are running late due to the fog situation.
"My flight was about to depart at 8:40 am but it is now scheduled to depart at 10:30 am...The reason they have given is mainly due to weather and fog," a passenger told ANI.
The Indian Meteorological Department said that the Palam and Safdarjung airports have reported 500-meter visibility.
Taking to 'X', the weather department wrote, "Delhi Palam (VIDP) and Safdarjung Airports are reporting 500 m visibilities at 0530 hrs IST of today, the 16th January."
As per the MeT department, fog is considered to be 'shallow' when the visibility stands up to 500 metres. 'Moderate' fog occurs when the visibility remains up to 200 metres.
As the visibility is up to 50 metres, the fog is categorised as 'dense'. It is categorised as 'very dense' when the visibility reaches below 50 metres.
(With inputs from ANI)
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