Dense fog, chilly winds deepen Delhi cold spell as minimum dips below normal

Safdarjung recorded 5.8°C while Palam fell to 4.8°C. IMD issued a yellow alert for Friday, warning of moderate to dense fog through the weekend.

Wintry conditions deepened in the Capital on Thursday, with dense fog and chilly northwesterly winds working in tandem causing the temperature to fall and extend the cold spell, the India Meteorological Department (IMD) officials said.

A fog hole lifted daytime temperatures slightly, but wind chill remained high. No western disturbance is expected till January 15, weather experts said. (Vipin Kumar/HT)

Safdarjung, considered representative of Delhi, recorded a minimum temperature of 5.8°C on Thursday, one degree below normal and down from 8.6°C recorded a day earlier. Palam recorded a lower minimum of 4.8°C, dipping below the 5°C mark. The IMD has issued a yellow alert for Friday, forecasting moderate to dense fog, with minimum temperatures expected to hover between 5°C and 7°C. Similar conditions are likely to persist over the weekend, it said. The lowest minimum at Safdarjung so far this season was 5.6°C, recorded on December 4 and 5.

While minimum temperatures fell, the maximum rose marginally due to a fog hole forming over the capital post noon. Safdarjung recorded a maximum of 17.5°C, which was two degrees below normal but 0.8°C higher than Wednesday. No station recorded cold-day conditions on Thursday. The lowest maximum was recorded at Palam at 14.5°C, which was 4.2°C below normal.

“Unlike Tuesday and Wednesday, no cold-day conditions were recorded in Delhi. The lowest maximum across the city was 14.5°C at Palam, which was 4.2°C below normal, thus not meeting the cold day criteria,” an IMD official said.

The IMD defines a cold day as when the minimum is below 10°C and the maximum departs from normal by 4.5°C or more, while a severe cold day is when the maximum is 6.5°C or more below normal.

Navdeep Dahiya, an amateur weatherman, attributed the marginal rise in the maximum to a fog hole over Delhi-NCR. “Despite this, the wind chill factor was high, keeping the maximum in check,” he said, adding that upper-level fog persisted across parts of Punjab, Haryana, Uttar Pradesh and northwest Rajasthan.

Dahiya said no western disturbance is expected till January 15. “For Delhi, till January 15, the maximum can hover between 12-15°C at Safdarjung and 10-14°C at Palam. The minimum should fall to around 3-4°C,” he said.

Visibility dipped to 100 metres at Palam due to dense fog, while Safdarjung recorded moderate fog with visibility of 500 metres, officials said. Winds of 5-10 kmph, briefly touching 15 kmph, marginally improved air quality, with the AQI at 280 (poor) at 4pm on Thursday from Wednesday’s 289, according to the daily national bulletin by Central Pollution Control Board (CPCB).

The Centre’s Air Quality Early Warning System (EWS) said AQI is likely to deteriorate to “very poor” on Friday. “Delhi’s air quality is likely to be in the ‘poor’ category from Saturday to Sunday. The outlook from January 12 onwards shows air quality between ‘poor’ and ‘very poor’,” it said.