Low temperatures and fog in Delhi hit air and rail movement this morning as a cold wave gripped the capital with minimum temperatures dipping as low as 5.6 degrees Celsius.
With visibility of just 50 metres (164 ft) in some areas, Delhi Airport took to Twitter to alert passengers that flights not equipped to operate in such conditions "may get affected".
Reports suggest that 15 trains to Delhi were also running late because of fog.
The India Meteorological Department or IMD said in a bulletin that "dense and very dense fog" was likely to continue over some parts of the city over the next 24 hours due to light wind and high moisture levels.
"Its intensity and spread (is) likely to reduce thereafter," the IMD said.
The IMD also forecast cold wave conditions in some areas over Punjab, Haryana and Delhi during the next two days.
A cold wave is declared in the plains when the minimum temperature dips to 4 degrees Celsius or falls 4.5 degrees Celsius below normal to 10 degrees Celsius or below.
