Delhi shivers at 10.4°C — coldest morning of the season yet

The IMD’s historical data for the first 10 days of November over the past several years shows that this year has witnessed an unusually sharp and early drop in night temperatures.

From 19.4°C on November 1, the minimum has fallen almost steadily each day to 12.7°C by November 6, 11°C on November 8, and finally 10.4°C on November 10. This marks a fall of about 9°C in just 10 days, making it one of the steepest early-November declines in recent years.

By contrast, during the corresponding period last year (2024), Delhi’s minimum temperature hovered between 17°C and 18°C, showing almost no decline through the first half of the month.

The situation was similar in 2022 and 2023, when the night temperature stayed well above 14°C until mid-November.

Only in 2020, when temperatures touched around 10°C in the first week itself, was there a comparable early chill. Between 2021 and 2024, Delhi had seen a trend of delayed or gradual onset of winter, with relatively warm first halves of November.

According to experts, this year’s sharper dip can be attributed to clear skies, dry northwesterly winds, and reduced humidity, which together can enhance radiational cooling during the night.

On Monday, the IMD said in its bulletin, “Westerly winds prevailed with wind speed upto 15 kmph in the past 24 hours over Delhi.”

Air quality update

The average air quality index (AQI) in Delhi was reported at 344 (‘Very Poor’) as of 9 am. A day before, the average AQI at 4 pm was 370.

Taking stock of the AQI reaching the upper end of the ‘Very Poor’ category, the Commission for Air Quality Management in NCR and Adjoining Areas reviewed the situation but decided not to evoke Stage III of the Graded Response Action Plan as the air quality thereafter showed an “improving trend”.

As per the CPCB, only Bawana station reported Severe AQI at 411. Other stations such as Wazirpur closely followed at 397 — in the upper end of the ‘Very Poor’ category.

Meanwhile, as per the IMD forecast, mainly clear skies are expected with mist or haze conditions in the morning hours. A few days will also see shallow fog conditions, it has said.

It has further forecast the temperatures to fall to around 9-11°C by Friday. The maximum temperature is expected to hover at 26-28°C.