IMD issues red alert; over 70 trains arriving in Delhi are delayed by up to 15 hours due to dense fog; see the complete list.

Dense fog enveloped the national capital, Delhi, on Monday morning. The India Meteorological Department (IMD) had issued an orange alert for Monday, which has now been upgraded to a red alert.

Visibility at Indira Gandhi International Airport and Safdarjung was only 50 meters until 8 am. The fog disrupted flight and train operations. Meanwhile, pollution levels also increased.

According to the Central Pollution Control Board's (CPCB) Sameer app, the Air Quality Index (AQI) was recorded at 402 at 8 am, falling into the 'severe' category. Anand Vihar (455) and Vivek Vihar (456) were the most polluted areas.

Due to the fog, 70 trains arriving in Delhi are running two to 15 hours late. The delayed arrival in Delhi has necessitated changes in the departure times of several trains for their return journeys. Several long-distance and local trains are also running late, causing inconvenience to daily commuters.

Major trains running late:

New Delhi-Barauni Humsafar Special - 14.05 hours

New Delhi-Kanpur Shram Shakti Express - 11.05 hours

New Delhi-Kalka Shatabdi Express - 4.25 hours

New Delhi-Amritsar Shan-e-Punjab Express - 5.25 hours

New Delhi-Sogaria (Kota) Superfast Express - 4.75 hours

New Delhi-Darbhanga Humsafar Special - 5 hours

Anand Vihar Terminal-Ayodhya Cantt Vande Bharat - 6.05 hours

New Delhi-Lucknow Swarn Shatabdi Express - 3 hours

New Delhi-Firozpur Intercity Express - 2 hours

Anand Vihar Terminal-Jogbani Seemanchal Express - 1.5 hours