Nights get cooler in Delhi, min temp to dip below 20°C soon: IMD

On Monday, Delhi recorded a minimum temperature of 20.1°C, three degrees lower than normal for this time of the year

With the southwest monsoon withdrawing from large parts of northwest India, cold northwesterly winds are blowing through the region, bringing down the night temperature in this sector, including the Capital, India Meteorological Department (IMD) officials said on Monday.

The India Gate lawns on a misty, cool morning. (Arvind Yadav/ HT PHOTO)

On Monday, Delhi recorded a minimum temperature of 20.1 degrees Celsius (°C), three degrees lower than normal for this time of the year, and two notches lower than Sunday’s low of 22.1°C.

IMD predicts that the mercury is likely to drop further, dipping below the 20-degree mark by the middle of the week.

The withdrawal of the monsoon from Delhi was officially declared on September 30.

“During the monsoon period, the wind direction is mainly easterly or southeasterly, but this changes to northwesterly once the withdrawal finishes. These are drier and much colder winds. The absence of moisture also leads to clear skies, which is making the days fairly warm, and nights cooler,” said Kuldeep Srivastava, scientist at IMD.

The warm days and cool nights that Srivastava was referring to was apparent on Monday — while the minimum was 20.1°C, the day’s high was 35.1°C, a swing of 15 degrees over the course of the day.

Srivastava added that the absence of a significant cloud cover above Delhi means that the surface heat generated during the day is dissipated into the atmosphere at night. At the same time, the northwesterly winds give the region a cooling effect, he said.

According to IMD data, the minimum temperature tends to dip below 20°C around the first or second week of October every year. By the last week, the minimum often drops below 15°C.

Last year, the lowest minimum temperature in October stood at 14°C, recorded on October 25.

IMD predicts that while Delhi’s maximum is expected to hover around 35-36°C till coming Sunday, the minimum temperature is expected to dip to 19°C by Thursday, before rising by 2-3 degrees on Saturday and Sunday, as the wind direction once again changes to southeasterly, Srivastava said.

“Overall, we are beginning to see a gradual dip in minimum temperature generally seen around this time of the year,” Srivastava said.

Mahesh Palawat, vice president at Skymet, a private weather forecaster, concurred with Srivastava’s assessment. “These dry (northwesterly) winds keep the days warm. But at night, there is a nip in the air. There is very little moisture and clear skies will further help increase this gap between the maximum and minimum temperatures,” said Palawat, adding that the minimum could dip to around 17°C in the second week of October.