New Delhi: The national capital continued to shiver on Thursday, even as the city recorded its coldest night in three years, with the minimum temperature plunging to 2.9 °C amid icy-cold northwesterly winds and dense fog.
Meanwhile, coldwave conditions stretched into a fifth day across the capital. The minimum temperature of 2.9°Celsius on Thursday was 4.5 degrees below normal for this time of the year — down from Wednesday’s minimum of 3.8°Celsius and Tuesday’s minimum of 3°Celsius.
The last time Delhi saw an ever lower minimum was January 18, 2023, when the mercury plummeted to 2.6°Celsius, according to India Meteorological Department (IMD) data.
Meanwhile, Palam logged a minimum temperature of 2.3°Celsius on Thursday, five degrees below normal and the lowest in 20 years. The station earlier recorded an even lower temperature of 0.3°C on January 8, 2006.
The IMD has issued a “yellow” alert for Friday, forecasting a slight rise in minimum temperatures to 4-6°Celsius. The temperatures may further rise to 5-7°Celsius on Saturday and 6-8°Celsius on Sunday due to warmer winds resulting from a western disturbance.
IMD classifies a “cold wave” when the minimum temperature is below 10°Celsius and at least 4.5°Celsius below normal, or when the actual minimum drops to 4°Celsius or lower.
According to IMD, the minimum stood at 2.7 °C at Ayanagar, while Lodhi Road and Ridge recorded lows of 3.4 °C and 4.5°C, respectively. “Multiple stations logged coldwave conditions on Thursday. There is a possibility that isolated pockets may record coldwave conditions on Friday as well. Relief is likely over the weekend,” said an IMD official.
The all-time minimum for Safdarjung in January is -0.6 °C, recorded on January 16, 1935. For Palam, the all-time low is -2.2 °C, recorded on January 11, 1967.
Officials said a combination of icy-cold northwesterly winds and dense fog impacted temperatures in the city on Thursday, with visibility at Palam dropping to 50 metres between 6 and 9 AM. Meanwhile, the lowest visibility at Safdarjung was 100 metres, recorded around 6 AM.
The impact of poor visibility was evident on both flights and train services. Data from Flightradar24 showed that over 500 flights were delayed at Delhi’s Indira Gandhi International (IGI) airport, with the average departure delay of 32 minutes. Over 50 trains were also running late, according to Northern Railways.
IMD classifies fog as “shallow” when visibility is between 500 and 1,000 metres; as moderate when between 200 and 500 metres. The fog is “dense” when visibility ranges between 50 and 200 metres, while visibility below 50 is considered “very dense”.
“The minimum will now start rising from Friday onwards. A second, more active western disturbance is meanwhile expected to bring possible rain across the plains on January 22 or 23,” said Mahesh Palawat, vice president at Skymet.
A western disturbance began impacting the Himalayan region from January 15, with fresh snowfall likely there on January 16. When a western disturbance approaches a region, it leads to a change in wind direction.
Cold northwesterly winds have been prevailing for about 10 days now, with the wind direction expected to shift back to easterly. Easterly winds bring moisture, but are far milder.
Meanwhile, Delhi’s air quality remained in the higher end of the “very poor” range on Wednesday. Overall, this was the third “very poor” air day in the city. The 24-hour average air quality index (AQI) stood at 343 (very poor) at 4 PM on Thursday. In comparison, it was 353 (very poor) at 4 PM on Wednesday.
Forecasts by the Centre’s Air Quality Early Warning System (EWS) for Delhi show deterioration ahead, with “severe” air quality likely on January 18.
“Delhi’s air quality is likely to be in the ‘very poor’ category from January 16 to January 17. The air quality is likely to be in the ‘severe’ category on January 18,” said EWS in its daily bulletin.