The national capital recorded a minimum temperature of 8.5 degrees Celsius on Saturday, a day after the city witnessed its coldest November morning in 14 years. The minimum temperature was four notches below the normal, according to India Meteorological Department (IMD) data.
Kuldeep Srivastava, head of the IMD's regional forecasting centre, said the minimum temperature was likely to increase Monday onwards under the influence of a fresh western disturbance. At 7.5 degrees Celsius, Delhi on Friday recorded its lowest minimum temperature in the month of November since November 29, 2006, when the city recorded a low of 7.3 degrees Celsius.
For the plains, the IMD declares a cold wave when the minimum temperature is 10 degrees Celsius or below and is 4.5 notches less than normal for two consecutive days. "However, for a small area like Delhi, a cold wave can be declared if the criteria is fulfilled even for a day," Srivastava said.
Delhi had recorded the lowest minimum temperature of 11.5 degrees Celsius in 2019, 10.5 degrees Celsius in 2018 and 7.6 degrees Celsius in 2017 in the month of November. The all-time record for the lowest minimum temperature in November is 3.9 degrees Celsius recorded on November 28, 1938.
Mahesh Palawat, an expert at Skymet Weather, a private forecasting agency, said cold winds blowing from snow-laden western Himalayas have led to a dip in the mercury, and a similar situation will continue till Saturday. A fresh western disturbance is approaching northwest India on November 23. It is likely to increase the minimum temperature by a few notches, he said.
The minimum temperature this month, barring on November 16, has remained 2-3 degrees below the normal in the absence of a cloud cover, according to IMD officials. Clouds trap some of the outgoing infrared radiation and radiate it back downward, warming the ground.
The month of October was the coldest in 58 years in the national capital. The mean minimum temperature in October this year was 17.2 degrees Celsius, the lowest since 1962, when it was 16.9 degrees Celsius..