A thick layer of fog engulfed Delhi and adjoining areas leading to reduced visibility on Monday because of that around 118 domestic flights and 29 trains were delayed. “Visibility recorded at 5:30 am today in Bhatinda-0 meters, Amritsar-25 and Ambala-25 meters each, Hissar-50 meters, Delhi (Safdarjung)-25 meters, Delhi (Palam)-50 meters; Uttar Pradesh: Agra-0 meter, Lucknow (Amausi)-0 meters, Varanasi (Babatpur)-25 meters, Bareilly-50 meters,” IMD said. However, talking about the air quality of Delhi on Monday AQI was recorded as in the ‘Severe’ category with an overall AQI of 422.