It was the coldest November night in over a decade on Friday with the minimum temperature settling at 7.5 degrees Celsius, which is five degrees cooler than the normal for the season.
In the past 14 years, the temperature has fallen below 8 degrees Celsius only thrice in — 2017, 2009 and 2006 — when it was 7.6, 7.9 and 7.3 degrees Celsius respectively. The Met department has forecast clear skies and cold wave-like conditions till November 22 after which a fresh western disturbance is expected that may help in increasing the temperature on November 23.
The Met said in the plains, the IMD declares a cold wave when the minimum temperature is 10 degrees Celsius or below and is also 4.5 notches less than normal for two consecutive days. If the criteria is met on November 21 as well, a cold wave will be declared in the Capital. This November has been colder with the minimum temperature settling constantly below average apart from on November 16.
The all-time record for the lowest minimum temperature in November is 3.9 degrees Celsius recorded on November 28, 1938. The maximum temperature was recorded at 25.4 degrees Celsius, which was two degrees below normal.
The air quality continued to be in the “poor category” and is likely to improve further due to an increased wind speed. The city’s 24-hour average air quality index was 296. It was 283 on Thursday, 211 on Wednesday and 171 on Tuesday, said Central Pollution Control Board.
Stubble burning
An AQI between zero and 50 is considered “good”, 51 and 100 “satisfactory”, 101 and 200 “moderate”, 201 and 300 “poor”, 301 and 400 “very poor”, and 401 and 500 “severe”. According to government-run body SAFAR, stubble burning accounted for 15% of Delhi’s PM2.5 pollution on Friday. It added that “energetic” surface winds are likely to influence AQI positively in the next two days.
