<p>The month of November was the coldest in the national capital in 71 years, with the mean minimum temperature dropping to 10.2 degrees Celsius, according to the India Meteorological Department.</p>.<p>Delhi had recorded a mean minimum temperature of 10.2 degrees Celsius in November 1949.</p>.<p>The mean minimum temperature for November was 9.6 degrees Celsius in 1938; nine degrees Celsius in 1931 and 8.9 degrees Celsius in 1930, according to IMD data.</p>.<p>Normally, the mean minimum temperature for the month of November is 12.9 degrees Celsius.</p>.<p><strong>Also Read: <a href="https://www.deccanherald.com/national/north-and-central/delhis-air-quality-in-very-poor-category-921578.html">Delhi's air quality in 'very poor' category</a></strong></p>.<p>The mean minimum temperature was 15 degrees Celsius last year, 13.4 degrees Celsius in 2018 and 12.8 degrees Celsius in 2017 and 2016.</p>.<p>Delhi also braved four cold waves in November –on the 3rd, 20th, 23rd and 24th. </p>.<p>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.</p>.<p>“However, for small areas such as Delhi, a cold wave can be declared if the criteria is fulfilled even for a day,” Kuldeep Srivastava, the head of the IMD's regional forecasting centre, said.</p>.<p>On Monday, Delhi recorded a minimum of 6.9 degrees Celsius. This is the eight-day this month that the minimum temperature remained below 10 degrees Celsius.</p>.<p>On November 23, Delhi recorded a minimum of 6.3 degrees Celsius -- its lowest minimum temperature in the month since November 2003, when the city recorded a minimum of 6.1 degrees Celsius, according to Srivastava. </p>.<p>The minimum temperature this month, barring on November 16, has remained 2-3 degree Celsius below normal in the absence of a cloud cover on most days, according to IMD officials.</p>.<p>Clouds trap some of the outgoing infrared radiation and radiate it back downward, warming the ground.</p>.<p>The month of October was the coldest in 58 years in the national capital. </p>.<p>The mean minimum temperature in October this year was 17.2 degrees Celsius, the lowest since 1962, when it was 16.9 degrees Celsius.</p>
<p>The month of November was the coldest in the national capital in 71 years, with the mean minimum temperature dropping to 10.2 degrees Celsius, according to the India Meteorological Department.</p>.<p>Delhi had recorded a mean minimum temperature of 10.2 degrees Celsius in November 1949.</p>.<p>The mean minimum temperature for November was 9.6 degrees Celsius in 1938; nine degrees Celsius in 1931 and 8.9 degrees Celsius in 1930, according to IMD data.</p>.<p>Normally, the mean minimum temperature for the month of November is 12.9 degrees Celsius.</p>.<p><strong>Also Read: <a href="https://www.deccanherald.com/national/north-and-central/delhis-air-quality-in-very-poor-category-921578.html">Delhi's air quality in 'very poor' category</a></strong></p>.<p>The mean minimum temperature was 15 degrees Celsius last year, 13.4 degrees Celsius in 2018 and 12.8 degrees Celsius in 2017 and 2016.</p>.<p>Delhi also braved four cold waves in November –on the 3rd, 20th, 23rd and 24th. </p>.<p>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.</p>.<p>“However, for small areas such as Delhi, a cold wave can be declared if the criteria is fulfilled even for a day,” Kuldeep Srivastava, the head of the IMD's regional forecasting centre, said.</p>.<p>On Monday, Delhi recorded a minimum of 6.9 degrees Celsius. This is the eight-day this month that the minimum temperature remained below 10 degrees Celsius.</p>.<p>On November 23, Delhi recorded a minimum of 6.3 degrees Celsius -- its lowest minimum temperature in the month since November 2003, when the city recorded a minimum of 6.1 degrees Celsius, according to Srivastava. </p>.<p>The minimum temperature this month, barring on November 16, has remained 2-3 degree Celsius below normal in the absence of a cloud cover on most days, according to IMD officials.</p>.<p>Clouds trap some of the outgoing infrared radiation and radiate it back downward, warming the ground.</p>.<p>The month of October was the coldest in 58 years in the national capital. </p>.<p>The mean minimum temperature in October this year was 17.2 degrees Celsius, the lowest since 1962, when it was 16.9 degrees Celsius.</p>