Cold winds impact Delhi-NCR, temperature drops below 16°C

Another western disturbance is expected to hit northwest India over the weekend, but added that it is unlikely to bring the Capital much rain

The Capital on Thursday clocked a minimum temperature of 15.9 degrees Celsius (°C) — three degrees below normal and the coolest October 19 over the last five years. This was also the earliest that Delhi’s minimum dropped below 16°C in the run-up to winter since 2014, when the temperature dipped to 15.6°C on October 17, showed India Meteorological Department (IMD) data available from 2011.

A foggy morning at Yamuna Bank on in Delhi on Thursday. (Sanjeev Verma/HT Photo)

The minimum on October 19 in 2022 was 17°C, while it was 19.9°C in 2021, 16°C in 2020, 19.8°C in 2019 and 17.8°C in 2018.

Another western disturbance is expected to hit northwest India over the weekend, IMD said, but added that it is unlikely to bring the Capital much rain and will impact temperatures only marginally.

The cooler nights are largely due to cool, northwesterly winds sweeping through the region, said Met officials. These also helped keep the day relatively cool, with a maximum temperature of 30.4°C, two degrees below normal and marginally lower than 30.7°C on Wednesday.

READ | Mercury below 20°C in Delhi, first time this season

“We can expect the minimum to remain around 16°C till Saturday and then gradually rise to 17-18°C by Sunday and Monday. But since the fresh western disturbance will be feeble, we will not see a spike in nighttime temperature,” said Kuldeep Srivastava, scientist at IMD.

At the Safdarjung station, considered representative of Delhi’s weather, the minimum temperature was 17.3°C on Wednesday, 17.2°C on Tuesday and 21.1°C on Monday. The minimum temperature at Safdarjung usually dips below 15°C towards the end of October.

The Ridge station in north Delhi was the city’s coolest spot on Wednesday, as the minimum temperature fell to 13.1°C, six degrees below normal.

READ | Delhi records poor air quality as minimum temperature dips to lowest this season

Last year, the lowest minimum in October was 14°C on October 25, similar to 2021, when it was 14°C too, on October 25. In 2020, the lowest minimum was 12.5°C on October 29.

A western disturbance brings moisture to a region which can bring down the maximum temperature and lead to a slight rise in minimum temperature, as heat gets trapped by the clouds. Since Wednesday, Delhi has been recording clear skies and cold northwesterly winds — factors that have led to a drop in the mercury again.

Despite the dip in temperature, Delhi’s air quality stayed in the “moderate” category, largely aided by strong surface winds during the day, which aided the dispersion of pollutants. Delhi’s 24-hour average AQI was recorded at 121 (moderate) on Thursday. It was 129 (moderate) on Wednesday and 89 (satisfactory) on Tuesday — a day where Delhi recorded light rain.

Forecasts by the Early Warning System (EWS) for Delhi — a forecasting model under the ministry of earth sciences, showed a gradual deterioration in AQI to “poor” is expected in the next 24 hours as winds become calm at night. “The outlook for the subsequent six days shows the air quality is likely to remain in the ‘poor’ category,” said EWS.

The Centre Pollution Control Board (CPCB) classifies an AQI between 0-50 as “good”, between 51 and 100 as “satisfactory”, between 101 and 200 as “moderate”, between 201 and 300 as “poor”, between 301 and 400 as “very poor”, and over 400 as “severe”.

Gusty winds accompanied by rain had lashed parts of the national capital on Monday, making the weather pleasant, also leading to tangible nip in the air as well.

Meanwhile, IMD announced on Thursday that the southwest monsoon has withdrawn completely from the country, four days after the normal date of October 15.