This January, Delhi airport saw most hours of dense fog in 9 years

In the past 11 years, the highest hours of dense or very dense fog in the month of January was recorded in 2014, at 121 hours. The lowest figure, 24 hours, was recorded in January 2019 as well as 2020.

In December and January together — the main months the national capital experiences winter fog — the airport recorded 128 hours of dense or very dense fog, the highest for these months, after 174 hours in the 2014-15 winter. The lowest number of fog hours over the past decade was recorded in the 2021-22 winter, at 27 hours.

According to R K Jenamani, scientist at IMD, the higher fog hours this winter was on account of two things that have been missing — western disturbances affecting the plains of northwest India, and wind at surface levels. No active western disturbances have affected the plains through the month, save for the system that brought rain to the national capital on Wednesday.

The normal dense or very dense fog hours in January — when visibility is usually less than 200 metres — is 66.3 hours.

During a press briefing on Wednesday, IMD Director General Mrutyunjay Mohapatra referred to this winter’s widespread fog cover — that has set in, starting December 25, over the Indo-Gangetic Plain — as the longest such fog spell in recent years. It persisted even on Wednesday when the visibility at the Delhi airport dropped to zero for a few hours.