Dipping mercury keeps Delhi shivering

Isolated parts of Delhi continued to experience cold wave conditions for a second consecutive day, with the minimum temperature continuing to drop across the Capital over the past 24 hours. At the Safdarjung station, considered representative of Delhi weather, a minimum temperature of 4.5 degrees Celsius (°C) was recorded on Monday, slightly down from 4.9°C recorded a day earlier and four degrees below normal for this time of the year.

This is the joint lowest minimum temperature recorded this season, as Delhi clocked 4.5°C on December 12 as well. The last time Delhi had a lower minimum in December was 3.2°C, recorded on December 20, 2021.

The India Meteorological Department (IMD) issued a “yellow” alert for the region till Wednesday, forecasting moderate fog and isolated cold wave conditions, and forecast the minimum to hover around 5°C.

Meteorological experts said clear skies were leading to a drop in temperature, but a marginal rise is likely from Tuesday due to the impact of a western disturbance, which is bringing moisture. Delhi reported shallow fog on Monday, with the lowest visibility recorded at 800 metres. A further dip in visibility in the early hours on Tuesday and Wednesday is likely, they said.

“Locally, Delhi had clear skies and northwesterly winds, so the temperature has been dipping. Now, with a feeble western disturbance impacting northwest India, the temperature may marginally rise. Although wind speeds have dropped, there is moisture in the air, which can trap heat,” said Mahesh Palawat, vice president at Skymet meteorology.

The maximum temperature was, meanwhile, recorded at 24.5°C, which was two degrees above normal for this time of the year and up from 23.2°C recorded a day earlier. IMD forecasted the maximum to hover around 23°C on Tuesday too, before dipping to 22°C by Wednesday.

How other stations fared

Although Delhi’s maximum and minimum temperatures are recorded at the Safdarjung station, other locations clocked even lower temperatures on the day. The lowest minimum temperature across the city was 3.5°C, which was recorded at west Delhi’s Pusa station, followed by 4°C at the Ayanagar station in southwest Delhi. Both these stations recorded cold wave conditions, IMD said.

IMD classifies it as a cold wave when the minimum temperature is below 10°C, with the departure also being 4.5°C or more below normal. It can also be called a cold wave if the minimum is below 4°C across the plains.

“Isolated stations recorded cold wave conditions and while Safdarjung is likely to record a minimum of around 5°C on Tuesday, isolated stations should be cooler and thus, may record cold wave conditions again,” an IMD official said.

To be sure, IMD forecasted a warmer-than-usual December across most of northwest India, including Delhi-NCR.

Mercury fell below 5°C for the first time this winter on December 11, when it was 4.9°C on the day. This is the fourth day now so far this season when the minimum temperature at the Safdarjung station has been below 5°C. On December 11, Delhi also recorded its earliest dip below the 5°C threshold since 1987, when the dip was recorded on December 6.