Safdarjung observatory recorded 4.2 degrees Celsius which was three notches below normal.
In Lodhi Road, the minimum temperature plunged to 3.3 degrees Celsius, whereas the weather stations at Ayanagar, Palam and Ridge recorded 3.5, 4.5 and 5 degrees Celsius respectively.
The maximum temperature today settled at 17.7 degrees Celsius, said a MeT official.
Moderate to dense fog during the early hours and forenoon disrupted rail services, leading to cancellation of 35 trains, including those which were earlier announced to be cancelled due to the fog, and delaying 14 others.
The MeT office has predicted mainly clear skies for tomorrow.
"The skies will be mainly clear. Moderate to dense fog would occur at a few places tomorrow. The maximum and minimum temperatures are likely to hover at 19 and 5 degrees Celsius," the weatherman said.