NEW DELHI: The national capital recorded the first cold day of the season on Saturday, December 18, 2021, with the day temperature dropping to 17.8 degrees Celsius — five notches below normal for this time of the year. Also, it recorded the lowest minimum temperature of the season so far at 6 degrees Celsius, as per the India Meteorological Department (IMD). The weather office has forecast cold days over the next two days while cold wave conditions to occur on December 20.
According to IMD officials, on Saturday, the Safdarjung Observatory, the base station for Delhi recorded the maximum temperature as 17.8 degrees C — five notches below the season’s average. The minimum was 6 degrees C, two notches below normal for this time of year. “The departure from normal was five degrees, which suffices the conditions required to declare a cold day. The normal maximum temperature for this time of the year is around 22.5 degrees C. Also the minimum temperature dropped to the lowest recorded in the season so far,” said RK Jenamani, senior IMD scientist.
The Palam weather station recorded maximum temperature of 16.4 degrees Celsius, six notches below normal for this time of the year, IMD data showed. According to meteorologists, a cold day is when maximum temperature departure from normal is 4.5 degrees C to 6.4 degrees C while the minimum temperature (in the plains) is less than 10 degrees C.
Besides, the criteria for cold wave is defined as when the minimum temperature departure from normal is 4.5 degrees C-6.4 degrees C or the minimum temperature is lesser than 4 degrees C.
“Delhi is likely to see cold days on December 19-20 as well while cold wave conditions are expected on December 20. The below normal weather is mainly on account of dry and cold northwesterly winds blowing from snow-clad mountains. There has been snowfall in the Western Himalayan Region as well as in parts of Jammu and Kashmir. NCR states and adjoining areas including parts of Rajasthan, Haryana and Uttar Pradesh (UP) are likely to see cold wave conditions over the coming days,” a senior IMD scientist said.
MeT officials also said that shallow fog was reported from the IGI airport in the early hours on Saturday with visibility reducing to 200-400 metres. The cold combined with high speed gusty winds throughout the day, also helped improve the air quality to ‘poor’ zone. Delhi’s 24-hour average air quality index (AQI) on Saturday was 291 in the poor zone, as against 329, the previous day.
“Gusty winds at a speed of 10-20kmph prevailed over Delhi-NCR in the first half of the day, gusting to 40kmph by afternoon. This helped disperse pollutants in the atmosphere. It is likely to improve further over next three days owing to good winds,” said a senior IMD official.
Delhi’s air quality over past month has consistently been ‘very poor’ with a minor improvement to ‘poor’ intermittently even though a slew of restrictions were in place since mid-November, as directed by the Commission for Air Quality Management (CAQM) in NCR and adjoining states.
Night patrols to check pollution arising from construction activities
Exempted services
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