Delhi awaits winter chill as mild December continues

On Tuesday, the maximum temperature was 28.2 degrees Celsius (°C) – three degrees above the season’s normal – and a notch above the 27.4°C a day earlier.

Delhi residents continued their long wait for the proper onset of winter as the city continued to experience both day- and night-time temperatures that remained unseasonably mild and remained above what is considered normal for this time for the year.

At the Qutab Minar on a relatively clear and sunny day in Delhi on Tuesday. (Arvind Yadav/HT Photo)

On Tuesday, the maximum temperature was 28.2 degrees Celsius (°C) – three degrees above the season’s normal – and a notch above the 27.4°C a day earlier. Meanwhile, the minimum temperature, which was 10.4°C on Monday, settled on 10.5°C on Monday – a degree above normal.

The lowest minimum so far this season was 9.5°C, which was recorded on November 28.

The India Meteorological Department (IMD) this week issued a forecast that December this year will remain mild, with both average maximum and minimum in the Capital expected to be above normal – similar to the rest of northwest India.

Meanwhile, the air quality index (AQI) remained in the “poor” category for third straight day in the Capital.

Delhi’s 24-hour average AQI was at 268 (poor) at 4pm – a slight improvement from Monday’s reading of 280 (poor) as strong winds of 15km/hr were recorded during the day. Delhi recorded a lower AQI last on October 26 at 255. Forecasts by the Centre’s Early Warning System for Delhi (EWS) show similar meteorological conditions are expected to prevail across Delhi-NCR in the next three days and the AQI will remain “poor”.

“Delhi’s air quality is likely to be in the ‘poor’ category from December 4 to December 6. The outlook for the subsequent six days shows the air quality will oscillate between poor and very poor,” the EWS said on Tuesday.

Mahesh Palawat, vice president at Skymet meteorology, said, “We saw strong surface winds, up to 10km/hr in the first half of the day and around 15 km/hr post noon. Similar wind speeds of 15 to 20km/hr are likely till Friday, with the AQI expected to improve even further.”

CPCB data at 4pm showed that out of the 37 air quality stations registered online, none were in the “severe” category while five of them were in “very poor” zone. The highest AQI reading was 322 (very poor), recorded Shadipur. The rest had an AQI below 300 and were in the ‘poor’ range.

Data from last year’s December showed that the average AQI of the month was 348, with three “severe” air days. The lowest AQI recorded last December was 286, while the highest was 450 on December 23. Generally, there is a spike in pollution in the second half of December, when temperatures dip below 5°C, wind speeds drop and dense fog returns to the region.

Meanwhile, the Centre for Research on Energy and Clean Air (CREA) released its analysis on air quality across the country in the month of November. The analysis stated that Delhi was the most polluted city across the country with a monthly average PM 2.5 concentration of 249 micrograms per cubic metre (µg/m3). This was the highest average for Delhi in November since 2016, when it was 254µg/m3 and nearly 2.2 times the average recorded in October 2016 at111µg/m3, the report said.

Delhi had ended November with an average AQI of 374, its second highest since 2021, when it was 376. The report further said that stubble burning contributed 19% to PM 2.5 levels in Delhi in the month of November this year.