It was a sunny and cold morning in the national capital on Wednesday with the minimum temperature recorded at 7.6 degrees Celsius, one notch above the season's average.
At least 18 trains were cancelled, 30 delayed and six rescheduled due to fog in several parts of northern India.
Humidity in Delhi at 8.30 a.m. was 95 per cent and visibility stood at 600 metres.
"The sky will be mainly clear during the day," an India Meteorological Department official told IANS.
The maximum temperature was likely to hover around 24 degrees Celsius.
The maximum temperature on Tuesday settled at 23.7 degrees Celsius, three notches above the season's average and the minimum temperature was recorded at 7.1 degrees Celsius.