A thick blanket of fog over the national capital reduced the visibility levels to below 100 metres, disrupting trains and flights for the second consecutive day."My flight is delayed by two hours. I am going to Srinagar. Reason for the delay in my flight schedule is bad weather and fog," said Amit, a passenger.Nineteen flights were cancelled and 650 flights were delayed by one to eight hours."My daughter is going to Ahmedabad and her flight has been delayed. We have come here from Meerut and we are facing lot of problems," said Alok Kumar, relative of a passenger.Train schedules were also affected with around 96 trains running late and 13 trains being cancelled either partially or entirely.Road traffic also moved at a snail's pace in several places, as the roads remained enveloped by thick fog leading to poor visibility.The Delhi airport was almost closed from 5:30 am to 11 am as visibility was recorded below 100 meters on Monday.North India usually witnesses early morning fog every winter when night temperatures often dip below five degrees Celsius.