On Friday, Delhi recorded its first ‘good’ air quality day this year, with an AQI of 47.
With intermittent rainfall over the day and strong winds, the AQI improved from 57, in the ‘satisfactory’ category on Thursday. The AQI has been in the ‘satisfactory’ category from September 11 onwards. AQI up to 50 is considered ‘good’, while AQI from 51 to 100 falls under ‘satisfactory’. ‘Good’ AQI has minimal impact on health, while ‘satisfactory’ AQI may cause “minor breathing discomfort to sensitive people”, according to the Central Pollution Control Board (CPCB).
Delhi recorded a single ‘good’ air quality day last year when delayed withdrawal of the monsoon and western disturbances brought rainfall to the city in October. In 2020, there were five days with AQI in the ‘good’ range, and the city saw two such days in 2019.
After what was a warm and humid two weeks this month, the maximum temperature fell sharply on Friday, settling at 25.9 degrees Celsius, which is eight degrees below normal for this time of the year at the Safdarjung weather station. This is down from 31.7 degrees recorded on Thursday, and more than ten degrees lower than the highest maximum temperature of 38 degrees recorded this month.
The maximum temperature recorded on Friday was also the lowest maximum temperature that the month of September has seen since at least 2011.
The weather stations in the city recorded only light rainfall during the day. Between 8.30 am and 5.30 pm, the Safdarjung weather station recorded 8.6 mm of rainfall, Lodhi Road recorded 8.3 mm and the Ridge recorded 5.4 mm. With no heavy rainfall so far this month, the city’s rainfall deficit remains high at 78% at Safdarjung. Cloudy skies are likely to persist Saturday, but no rainfall is expected, according to the IMD.