Twenty four trains are running late, five have been rescheduled and one has been cancelled due to foggy weather in the national capital on Monday.
Six international and eight domestic flights at the IGI Airport have also been delayed following poor visibility.
The temperatures in the national capital have plunged below normal levels in the past two days.
Yesterday was the coldest night of this winter so far, with the minimum temperature recorded at 7.2 degrees Celsius.
Both maximum and minimum temperatures yesterday were 4 degrees less than those recorded a week ago.
According to MeT officials, the reason for the change has been north-northwesterly winds that have been transporting cold from the north.
However, a further dip in temperature is unlikely over the next three-four days. A western disturbance is likely to hit northern India around 22nd December and temperatures are likely to dip thereafter.