Dense fog covered Delhi and large parts of the National Capital Region on Monday, sharply reducing visibility and badly affecting daily life. Roads, railways and air travel were all hit, while the cold weather added to the discomfort of residents.
The heavy fog led to 128 flights being cancelled at Delhi airport, including 64 arrivals and 64 departures. At least eight flights were diverted to other cities as pilots were unable to land in the poor visibility. Airlines also issued advisories asking passengers to check flight timings before leaving for the airport, and warned that operations could be slower than usual.
Several trains heading towards Delhi also ran late, with reports saying that around 100 trains were delayed because of the weather. 
The India Meteorological Department has placed Delhi under an orange alert for very dense fog. The maximum temperature is expected to be around 22°C, while the minimum may drop to nearly 7°C. Parts of Uttar Pradesh and Uttarakhand are also under the same alert.
In Noida, thick fog settled over the city from Sunday night and continued into Monday morning. Visibility fell sharply on major roads and expressways, including the Noida–Greater Noida Expressway and the Yamuna Expressway, making driving difficult. As a precaution, the local administration ordered schools to remain closed from December 29 to January 1.
The severe fog also affected air quality in the national capital. The Air Quality Index (AQI) touched 403, which falls under the ‘severe’ category. Some areas recorded even worse levels, including Anand Vihar, which reported an AQI of 459. Other stations such as ITO, Chandni Chowk, IIT Delhi and Lodhi Road also showed very poor to severe readings.
Residents across Delhi-NCR reported slow traffic, long delays, and poor visibility during morning hours. Authorities have advised people to drive carefully, use fog lights and avoid unnecessary travel during low-visibility periods.
