New Delhi: Flights were cancelled, trains ran late and road traffic was sluggish as Delhi was enveloped in a thick fog blinding it for as long as 12 hours, starting late Friday night. This was the season’s worst fog situation for the national capital. India Meteorological Department has issued a yellow alert for moderate to dense fog on Sunday late night, while light rain is likely the next day.
Commuting was tough on the city’s roads and many people were seen stranded during the fog hours.
According to India Meteorological Department, very dense fog led to zero visibility for nine hours in Palam and six hours in Safdarjung. At IGI Airport, zero visibility lasted from 11:30 pm on Friday to 8:30 am the next day. By 9 am, the visibility improved only to 50 metres. The situation led to the cancellation of 45 flights, diversion of 19 and delay of over 400 flights. The Safdarjung airport recorded zero visibility from 2.30 am to 8.30 am, which improved to 100 metres at 9 am.
Prior to Saturday’s fog episode, Jan 14, 2024 saw a similar fog situation in Delhi when very dense fog conditions with zero visibility lasted for nearly 6 hours.
Weather scientists cited no winds, an abundance of moisture near the surface layer, and a highly stable surface boundary layer as the reasons for this fog situation.
Earlier on Friday, Delhi witnessed very dense fog with visibility dropping to zero at Palam between 8 am and 9:30 am.
Senior IMD scientist RK Jenamani said that fog conditions also remained worse across many areas of the Indo-Gangetic plains region, mainly over the plains of northwest India, extreme parts of north Madhya Pradesh and Uttar Pradesh, and west Bihar. Airways, railways and roadways were affected in these areas too.
On Saturday, Safdarjung, the city’s base station for weather, recorded a minimum temperature of 7.8 degrees Celsius, 0.9 notches above normal, against 7 degrees Celsius a day earlier. The maximum temperature was 20 degrees Celsius, 0.7 notches above normal, against 21.2 degrees Celsius. The minimum and maximum temperatures on Sunday are likely to hover around 18 and 10 degrees Celsius, respectively.
Meanwhile, the national capital’s air quality remained in the very poor category. Fifteen out of 37 monitored areas, however, suffered severe air quality levels by Saturday evening due to the aggregation of pollutants and weather conditions unfavourable for their dispersion.
The average air quality index (AQI) was 378 on Saturday, the same as a day earlier. An AQI between zero and 50 is considered good, 51 and 100 satisfactory, 101 and 200 moderate, 201 and 300 poor, 301 and 400 very poor, and 401 and 500 severe.
The air quality may remain in the poor to very poor range during the next week. “The air quality is likely to be in the very poor category from Jan 5 to 6. It is likely to be poor on Jan 7. During the subsequent six days, the air quality is likely to be in the poor to very poor category,” stated IITM’s advanced air quality monitoring system.
