Heavy fog in India's capital, Delhi, has triggered travel disruptions, causing inconvenience for both air and rail commuters.

Reports indicate that approximately 50 flights and nearly two dozen trains have experienced delays due to the dense fog.

According to data from the flight tracking app flightradar24, departing flights faced an average delay of 25 minutes, while flight arrivals were delayed by eight minutes.

Passengers have expressed frustration over being stranded at the airport for extended periods.

Delhi airport authorities issued a flight advisory on Monday, advising passengers to contact their airlines for the latest flight updates.

The advisory highlighted that while landings and take-offs continue at Delhi airport, flights not compliant with CAT III standards may face disruptions. CAT III runways enable planes to land safely during low-visibility conditions.

In December, fog and poor visibility in the city had resulted in more than 100 flights being delayed. The airport witnessed massive travel chaos in January too, with dozens of people taking to social media to complain about delays and cancellations.

On Wednesday morning, videos and photos from different parts of Delhi and suburbs showed a blanket of fog covering many roads and obscuring buildings. The Indian Meteorological Department (IMD) said the visibility had dropped to zero in several localities.

The IMD has predicted light rains or thundershowers, accompanied by gusty winds, on Wednesday. The department has also predicted moderate fog for the next few days.

Dense fog is common in Delhi and the rest of north India during winters, but the cold in Delhi this season has tumbled many records.

An IMD report says Delhi has experienced the coldest January in 13 years with maximum temperature recorded at 17.7C. The second coldest January was nine years ago - in 2015 - when a maximum temperature of 17.9C was recorded in the city. Nights too have been coldest this year after 2013, the report adds.

Too bad.