Dense fog disrupted air operations in the national capital early on Friday morning and several trains continued to run late due to foggy conditions across northern India.
A thick blanket of fog enveloped the Palam area around 6am, delaying several flights for some time, Indira Gandhi International Airport sources said.
However, fog was feeble in other parts of the city.
Some trains were cancelled and several others were running behind schedule, Northern Railways sources said.
The minimum temperature in Delhi rose by over a degree Celsius to seven, which is normal, Indian Meteorological Department officials said.