Dense fog hampered flight operations at the Indira Gandhi International Airport in Delhi on Tuesday. Visibility was reduced to below 50 metres and many flights were delayed.
Four flights had to be diverted to nearby airports at Jaipur, Lucknow and Ahmedabad. There were, however, no fog related cancellations.
Fog started to descend at the airport around midnight and visibility became poor following which low visibility procedures (LVP) were implemented. The LVP period continued for nearly 10 hours and was only lifted by 10.15 in the morning.
A total 184 flights operated during this period using different categories of the Instrument Landing System (ILS), which guides pilots in landing during poor visibility. The CAT IIIB ILS, which operates in visibility as low as 125 metres, was used to operate 34 flights.
February is witnessing unusually foggy days even when December and January saw record low dense fog hours.
The met department said the late onset of western disturbances is to blame for this phenomenon.
The weatherman has predicted that visibility is likely to reduce to 400 metres at the airport after 3.30am on Wednesday and dense fog conditions will remain between 6.30am and 8.30am. Visibility is expected to improve slightly after 9.30am.