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Delhi and surrounding national capital regions (NCR) woke up to another harsh winter morning on Monday, December 29, as dense fog combined with toxic smog, severely reducing visibility and pushing air quality back into the ‘severe’ category.
The India Meteorological Department (IMD) issued a red alert for dense fog in Delhi for the next one hour, warning commuters of hazardous travel conditions.
Visibility deteriorated sharply late Sunday (December 28) night and remained extremely poor through the early hours of Monday, making road travel slow and risky across large parts of the National Capital Region.
Visibility drops across Delhi-NCR
Thick haze was reported from several locations, including the AIIMS flyover in Delhi and Sector 37 in Noida, where vehicles were seen moving cautiously with headlights barely cutting through the smog.
The foggy conditions compounded existing pollution levels, intensifying health concerns for residents.
AQI turns ‘severe’
Delhi’s air quality slipped into the ‘severe’ category, with the overall Air Quality Index (AQI) recorded at 403 on Monday, according to data from the Central Pollution Control Board (CPCB).
Read more: Delhi airport issues fog advisory for Monday; baggage system glitch hits T1 and T3
At least 25 monitoring stations reported AQI levels above 400, led by Vivek Vihar (460), Anand Vihar (459), Rohini (445) and Wazirpur (444), indicating extremely hazardous air quality across wide stretches of the capital.
Trains running late
Rail services were also affected due to poor visibility. Several long-distance trains, including the Rajdhani Express, Vande Bharat and Jan Shatabdi, were delayed as fog disrupted rail operations in northern India.
In some instances, trains were reported to be running late by over eight hours, news agency ANI reported citing passengers.
Flight operations impacted
Air travel at Delhi’s Indira Gandhi International (IGI) Airport was hit hard by low visibility. Airport authorities said that flight operations were being conducted only under CAT III conditions, which permit landings and take-offs in very low visibility.
Runway visibility in the morning was reported to be between 100 and 150 metres, according to Delhi airport, as per News18.
Passengers were cautioned about possible delays and cancellations. Authorities said additional ground staff were deployed across terminals to assist travellers and manage congestion, advising passengers to check flight updates directly with airlines.
Several carriers issued advisories. IndiGo said Delhi and Hindon airports were blanketed by fog and cold winter air, leading to schedule changes and slower operations.
Air India also warned of potential delays, diversions and cancellations due to dense fog across northern India.
Meanwhile, an Air India Express flight from Goa’s Mopa Airport was diverted to Ahmedabad after being unable to land in Delhi due to fog and congestion at alternate airports.
The India Meteorological Department (IMD) issued a red alert for dense fog in Delhi for the next one hour, warning commuters of hazardous travel conditions.
Visibility deteriorated sharply late Sunday (December 28) night and remained extremely poor through the early hours of Monday, making road travel slow and risky across large parts of the National Capital Region.
Visibility drops across Delhi-NCR
Thick haze was reported from several locations, including the AIIMS flyover in Delhi and Sector 37 in Noida, where vehicles were seen moving cautiously with headlights barely cutting through the smog.
#WATCH | Delhi | Visibility in the national capital is affected as a layer of toxic smog engulfs the city. CPCB claims that the AQI in the area is at '318',
categorised as 'Very Poor'.
(Visuals from Dwarka) pic.twitter.com/7r2mtzBY9Y
— ANI (@ANI) December 29, 2025
The foggy conditions compounded existing pollution levels, intensifying health concerns for residents.
AQI turns ‘severe’
Delhi’s air quality slipped into the ‘severe’ category, with the overall Air Quality Index (AQI) recorded at 403 on Monday, according to data from the Central Pollution Control Board (CPCB).
Read more: Delhi airport issues fog advisory for Monday; baggage system glitch hits T1 and T3
At least 25 monitoring stations reported AQI levels above 400, led by Vivek Vihar (460), Anand Vihar (459), Rohini (445) and Wazirpur (444), indicating extremely hazardous air quality across wide stretches of the capital.
Trains running late
Rail services were also affected due to poor visibility. Several long-distance trains, including the Rajdhani Express, Vande Bharat and Jan Shatabdi, were delayed as fog disrupted rail operations in northern India.
In some instances, trains were reported to be running late by over eight hours, news agency ANI reported citing passengers.
#WATCH | Delhi | A passenger, Gagan, says, "I have to go to Kanpur, but the train is running late by eight hours due to dense fog..." https://t.co/AYcgNWuyRm pic.twitter.com/9IhaGrz8y3
— ANI (@ANI) December 29, 2025
Flight operations impacted
Air travel at Delhi’s Indira Gandhi International (IGI) Airport was hit hard by low visibility. Airport authorities said that flight operations were being conducted only under CAT III conditions, which permit landings and take-offs in very low visibility.
Runway visibility in the morning was reported to be between 100 and 150 metres, according to Delhi airport, as per News18.
Passengers were cautioned about possible delays and cancellations. Authorities said additional ground staff were deployed across terminals to assist travellers and manage congestion, advising passengers to check flight updates directly with airlines.
#WATCH | Delhi | As cold waves grip the national capital, few flights are delayed at IGI Airport due to fog.
(Visuals from Indira Gandhi International Airport) pic.twitter.com/0Zlvs7gzlR
— ANI (@ANI) December 29, 2025
Several carriers issued advisories. IndiGo said Delhi and Hindon airports were blanketed by fog and cold winter air, leading to schedule changes and slower operations.
Air India also warned of potential delays, diversions and cancellations due to dense fog across northern India.
Meanwhile, an Air India Express flight from Goa’s Mopa Airport was diverted to Ahmedabad after being unable to land in Delhi due to fog and congestion at alternate airports.
#WATCH | Ahmedabad, Gujarat | Visuals from the Ahmedabad Airport, where passengers are affected amid flight disruption due to persistent dense fog. https://t.co/HuP71tuqSV pic.twitter.com/pHYALDdaHT
— ANI (@ANI) December 29, 2025
