Parts of northern India remained shrouded in dense fog for the third consecutive day, with zero visibility in the morning hours, leading to disruptions and delays in road, rail, and flight services. The much-needed incessant rain, the first of the season, in the afternoon aggravated foggy conditions further in northern India, including Delhi and the NCR.

Due to almost zero visibility, traveller and daily commuters faced a harrowing time traveling from one place to another. As many as 250 flights were delayed at Indira Gandhi International Airport, with at least three flights being diverted, as the disruption index went up to 3.0, according to the flight tracker information system. Massive chaos erupted at Delhi airport on Wednesday as passengers staged a protest and raised slogans against IndiGo airline after it cancelled a Deoghar-bound flight. The flight was scheduled to take off from Delhi airport’s Terminal 2.

Delhi received 8.5 mm of rainfall on Wednesday as the national Capital witnessed incessant rainfall accompanied by gusty winds with speeds of up to 30-40 kmph.

The incessant rainfall further aggravated cold day conditions. Weather fluctuations are expected to continue until February 3 because of a western disturbance, with further changes anticipated thereafter, according to the India Meteorological Department (IMD). Rainfall over northwest India during January 2024 (3.1 mm) was the second lowest since 1901, as per the IMD.

The IGI airport witnessed long queues of passengers waiting to get updates about their flights. Many passengers were seen waiting at the airport with their luggage. The disruption index went up to 3.0, according to the flight tracker information system. According to airport sources, a total of five flights were diverted to various destinations between 9:30 pm on Tuesday and 7 am on Wednesday.

Out of these, three were diverted to Jaipur in Rajasthan, and one each to Ahmedabad in Gujarat and Mumbai in Maharashtra. For arrivals, around 95 flights were delayed, and 15 were cancelled.

Zero visibility was reported at Indira Gandhi Airport at 6:30 am as a thick layer of fog engulfed the area. The visibility remained the same until 9 am, according to airport officials.

Owing to the dense fog conditions and low visibility, the Delhi airport has issued an advisory for passengers. It said, “While landings and take-offs continue at Delhi Airport, flights that are not CAT III compliant may be affected. Passengers are requested to contact the airline concerned for updated flight information. Any inconvenience caused is deeply regretted.”

In a video viral on social media, a group of passengers can be heard raising slogans like “IndiGo haye haye” and “bandh karo bandh karo”. Earlier in the day, IndiGo issued an advisory and said that flight operations in Delhi, Srinagar, and Chandigarh are likely to be impacted due to inclement weather. “Please check your flight status before leaving for the airport,” IndiGo said.

According to the India Meteorological Department (IMD), fog is formed when air at or near the earth’s surface becomes saturated by any of the three processes — cooling, addition of moisture, or mixing with another air parcel. Generally, fog forms in a stable air mass environment.

The minimum temperature was recorded at 7.3 degrees Celsius, a notch below the season’s normal on Wednesday morning, while the maximum temperature was settled at 18.3 degrees Celsius, four notches below the normal. The minimum temperature in Palam was settled at 9.4 degrees Celsius, Ayanagar at 9 degrees Celsius, and Ridge at 8.4 degrees Celsius, two notches below the normal.

Delhi witnessed a bone-chilling January in 2024, as most days were cold and sunless due to the fog this month. Very poor air quality, heavily foggy mornings, and bitter cold defined January 2024, making this month the coldest in terms of daytime, or maximum, temperature since 2003. The national capital recorded its coldest January in 21 years in terms of day temperatures.

The mean maximum temperature in January at Safdarjung was 17.9 degrees Celsius. It was the same as in 2015 and the lowest since 2003. The normal maximum temperature in January is 20.1 degrees Celsius, 2.2 degrees higher than what was recorded this month.

This January also saw the coldest minimum or night temperature since 2013. The mean minimum temperature this month was 6.43 degrees Celsius, which came with five cold days and five cold waves. This means the city experienced the highest number of days with extreme weather conditions in January in at least a decade.

IMD’s data shows that in the last 32 years, the average maximum temperature in January dipped below 18 degrees Celsius only thrice. Both January 2024 and 2015 recorded a mean maximum temperature of 17.9 degrees Celsius, just 0.3 degrees higher than in January 2003. January also saw several spells of cold conditions. Safdarjung, which is the city’s base station, recorded a total of 10 extreme weather events --- five “cold days” and an equal number of cold wave days --- making it the highest number of such days recorded in January in at least 12 years. Isolated parts of Delhi experienced cold day conditions for nearly 10 days.