A thick blanket of fog enveloped the national capital on Tuesday morning, reducing visibility on the streets and severely disrupting air and rail traffic.
The minimum temperature was recorded at 7.7 degree Celsius.
The railways cancelled six trains and rescheduled the departure timings of close to 50 trains.
According to a Northern Railway spokesperson, more than 80 trains, including the Rajdhani and the Shatabdi Express, arrived in the city several hours behind schedule.
At the airport, low visibility conditions were in place for a little over 17 hours during which time 433 flights operated. These included 21 flights under CAT-IIIB conditions (for visibility below 50m) and 64 under CAT-IIIA conditions.
Road traffic also moved at a snail's pace in several places, as the roads remained enveloped by thick fog leading to poor visibility.
North India usually witnesses early morning fog every winter when night temperatures often dip below five degrees Celsius.