Dense fog in the morning delayed 10 flights and affected the movement of about 100 trains in the capital which saw a more or less overcast sky Monday.
The Met department has forecast a clear Tuesday.
Visibility in the morning dropped to 50 meters, delaying some trains for over six hours. Road traffic was affected too with vehicles moving at a snail's peace early morning.
"Till 11 a.m. visibility was low and I was riding very slowly," said Mukesh Sharma, a resident of Rohini in north Delhi.
It was not very cold as the maximum temperature was recorded at 20.7 degrees Celsius, one notch above the average. The minimum temperature was 9.4 degrees Celsius -- two notches above the season's average.
The Met department predicted that Tuesday morning will be foggy followed by clear skies later in the day.
Tuesday's maximum and minimum temperatures are expected to hover around 21 and 8 degrees Celsius, respectively.