Science & TechClimate
Rain washes Delhi's air clean, AQI falls to 86 in 'satisfactory' band
A western disturbance brought thunderstorms on Thursday, pushing the capital's air quality into the satisfactory range on Friday morning and leaving October with nearly three times its normal rain.
Key points
- Delhi's AQI stood at 86 at 9:30 am on Friday, in the satisfactory category, by CPCB data.
- The Ridge recorded the most rain, 25.2 mm in 24 hours.
- The weather office expects Delhi to stay dry from 17 to 22 October, including Dussehra.
Delhi woke up to clean air on Friday. After thunderstorms swept the capital on Thursday, the Air Quality Index stood at 86 at 9:30 am, in the “satisfactory” band, according to Central Pollution Control Board (CPCB) data.
That is a sharp turn from earlier this month. On 4 October the city’s average AQI had climbed to 187, its worst in nearly three months, with stations such as Mundka in the “poor” range.
A wet October
The rain came from an active western disturbance over north Punjab and a cyclonic circulation over south Haryana. In the 24 hours to 8:30 am on Friday, the Ridge station recorded 25.2 mm, Lodhi Road 20 mm, Safdarjung 15.9 mm and Palam 11.2 mm.
Delhi has now received 65.8 mm of rain in October, against a monthly normal of 24.2 mm, nearly three times the usual amount. Daytime temperatures fell sharply. Safdarjung’s maximum on Thursday was 28.3°C, 4.9 degrees below normal and about six degrees cooler than Wednesday. Friday’s minimum was 19.4°C, while the Ridge dipped to 17.7°C.
Dry days ahead
The relief may not last long. The India Meteorological Department expects partly cloudy skies with light drizzle in places on Friday, followed by a dry spell from 17 to 22 October, including Dussehra on 20 October. Dry weather and calm winds usually let pollution build up again, and farm fires in Punjab have been rising with the paddy harvest.
On the CPCB scale, an AQI of 51 to 100 is “satisfactory”, 101 to 200 “moderate” and 201 to 300 “poor”.