It was a deep fog around the Delhi-NCR on December 31, 2025 and the visibility is even below zero, which makes a great commotion in the transport networks. It went to a red alert of heavy fog by India Meteorological Department (IMD), AQI rating was soaring to severe of 450 and above and schooling was canceled and the endangered people were called to remain back. The Iraqi stagnant winds and the burning of stubble with this cocktail winter seasonal smog is one of the latest eruptions of winter in the last few years since it is a snarl up of the national capital area.

The Visibility and Safety by fog Grip.

It had also brought down visibility to less than 50 meters in major airports such as IGI Delhi and Palam in the early morning hours leading to more than 150 flight delays and 20 diversion till noon. Highways such as Delhi-Agra Yamuna Expressway which had witnessed 15 accidents and NH-44 being crammed with massive traffic congestions were encountered. The commuters were subjected to gridlock time hours and the trains such as Rajdhani had to run as late as 4-6 hours. IMD data indicate that the fog is a combination of particulates of the pollution and moisture, which were formed at as low a temperature as 4 o C.

The police of Delhi came up with a rescue when they requested people to not travel unless they had to and they even stated that they lit lights which fogged roads. The DCP Traffic had declared that 0-50m visibility was not to be exceeded due to heavy fog; stay off the roads or drive slowly.

Affect on Air Transport and Rail Transport.

The most affected were IndiGo and Air India scripts and 30+ flights and international routes that were most affected with the worst hit being the Dubai and London. The customers took it to the social media where they encountered thousands of them in terminals. The railway announced controlled speed and this affected 200+ trains. The fog cloud that continued till 11 AM was cleared off at noon but according to IMD satellite, it reformed in the evening.

Affected Sector	Interruption	Key Stats
Airports	150+ hold-ups, 20 diversions	Visibility below 50m
Highways	5 accidents, congestion,1	NH-44
Trains	200+ late	4-6 hr delays
Schools	Shut	NCR-wide

Health hazards of Toxic Smog.

The AQI was 450 in Anand Vihar and PM 2.5 was in the extreme range of 600 -25x safe limit of 600 µg/m 3. Physicians do not encourage respiratory disorders, asthma activities and eye irritations in children and the elderly. AIIMS had recorded 20 percent increase in OPD. Stubble burning in Punjab-Haryana is a source of 40 percent of the pollution during the winter season besides industrial unit and vehicle emission pollution.

Theories of Motives A cloudy Overcast.

The trapped pollutants on the indo-gangetic plain are aggravated by the pollutants of the Diwali firecrackers and the farm fires that were at their peak courtesy of cold easterly winds. IMD makes long periods of chills on long periods of La Nina. This was due to GRAP Stage IV that banned the non-CNG cars and construction invoked by the Delhi govt last week.

Government Measures and Response.

CM Atashi declared an emergency of the free clinic and free masks. January 1 saw the introduction of odd-even in CAQM that had paralyzed half of the industry. Drones started dropping mist of water into the hotspots. GRAP very hard on contamination opined Environment Minister.

Travel Tips for Foggy Days

• Other sites such as Google Maps need to be revised.
• Car fog lamp; keep a distance of 50m.
• Check-in IRCTC/ airline applications.
• Wear N95 out in the streets; drink water.

Winter Forecasting and Long-term Solutions.

IMD predicts fog until January 5 with a minimum of 3-5 o C. The electric mobility, crop residue technology and regional airshed plans are long-term initiatives that are propelled by the professionals. The green cover of Delhi, which is being pushed with 10M trees, is of a mitigation nature.

Delhiites will be prepared to endure foggy mornings since it will be hazy towards the end of 2025. The weather is clear, not likely till New Year: keep in the shroud.