More than 200 flights were delayed, at least 30 cancelled, and several others were diverted.

“IGIA experienced Category IIIB, very dense fog, when visibility fell to below 50 m and runway visual range (RVR) ranged between 75-200 m between 1.30 am and 11.30 am on runway 29, and from 3 am to 11 am on runway 28,” R K Jenamani, director-in-charge, IGI Met Department said. According to the Met department, the fog is of a peculiar nature and is leading to swift changes in weather patterns. “The fog today was a ‘catchy-type’ cloud, which is associated with high wind speed,” Jenamani said. The RVR improved to 1000 m after 8 am, improving visibility considerably, but fell to 125 m at 9 am. “Fog finally cleared around 11.30 am,” he said.

Kingfisher Airlines had to cancel four flights and divert one and combine two due to bad weather. Five other flights, two domestic and three international, were also diverted.

“6E132 from Bangalore was diverted to Jaipur, G8173 from Goa was diverted to Jaipur, IC896 from Dubai was diverted to Jaipur, 9W 547 from Dubai was diverted to Mumbai and AI 112 from Lahore was diverted to Mumbai,” an airport official said.

Passengers of the London-Lahore-Delhi AI 112 flight protested after they were made to wait at Mumbai Airport on Thursday evening for hours. “We were supposed to reach Delhi Airport around 11 am but air traffic was congested. Our flight was made to hover for around 2 hours. Then, we were told the plane was running out of fuel and there was a need to land at Mumbai for refuelling,” said Md Ali Khan, a passenger on board AI 221. In Mumbai, the passengers said, they were made to wait for hours without food or drink in the aircraft.

Other passengers said they were not informed of delays.