Dense fog has blanketed parts of North India, significantly affecting both flight and train operations as visibility and temperatures drop. At Delhi's Indira Gandhi International Airport, over 200 flights were delayed due to zero visibility.

The India Meteorological Department (IMD) reported that Delhi's maximum temperature was 16°C, three degrees below the average, with a minimum of 7.6°C. The capital is expected to experience fog until January 8, with light rain forecast for January 6. On Friday morning, temperatures were recorded at 9.6°C, marking the fifth consecutive cold day in the city.

At 8 am, visibility at Palam airport in Delhi was reported at zero meters, while Safdarjung Airport recorded 50 meters of visibility. These airports, however, do not handle commercial flights. According to the Central Pollution Control Board (CPCB), Delhi's air quality index (AQI) at Lodhi Road station was 309, categorized as 'Very Poor.'

As a result of the dense fog, airlines such as SpiceJet, IndiGo, and Air India reported delays, with an average delay of six minutes for arrivals and 47 minutes for departures at Delhi Airport, according to FlightRadar24. SpiceJet flights to and from Amritsar and Guwahati were severely affected, while IndiGo issued a travel advisory, particularly for routes to Delhi, Amritsar, Lucknow, Bengaluru, and Guwahati. Passengers were advised to check their flight schedules before traveling, with the possibility of cancellations due to poor visibility.

Train services from and to Delhi were also impacted, with at least 24 trains delayed. The Ayodhya Express, for example, was delayed by four hours, while the Gorakhdham Express and other trains like the Bihar Kranti Express and Shram Shakti Express experienced delays of over two hours.

The dense fog is expected to persist in Delhi, Lucknow, Bengaluru, Amritsar, and Guwahati. The IMD issued a Nowcast warning for dense to very dense fog in several regions, including Rajasthan, Punjab, Haryana, and parts of Himachal Pradesh and Ladakh, where light rain and snow are anticipated.

In light of the cold wave, the Gautam Buddh Nagar administration has suspended classes in all schools in the district until further notice, with temperatures expected to dip to 8°C on Friday.