A thick blanket of dense fog enveloped Delhi Friday morning, reducing visibility to zero which impacted air and train operations, according to officials.
They said over 100 flights were delayed at the Indira Gandhi International Airport and 26 trains were running late.
According to the India Meteorological Department, "Zero visibility has prevailed over Palam since 4.30 IST with southeasterly winds blowing at 6-8 kmph."
At Safdarjung, visibility remains limited to a minimum of 50 meters in dense fog since 5.30 IST with calm winds, the IMD added.
Meanwhile, Delhi recorded a minimum temperature of 6 degrees Celsius, 0.9 notches below normal, while the air quality was recorded in the severe category.
According to the CPCB air quality bulletin, the AQI at 9 am was recorded in the "severe" category with a reading of 408.
The weatherman has forecast very dense fog for the day , with the maximum temperature expected to settle around 16 degrees Celsius.
An AQI between zero and 50 is considered "good", 51 and 100 "satisfactory", 101 and 200 "moderate", 201 and 300 "poor", 301 and 400 "very poor", and 401 and 500 "severe".