A spell of heavy rain and strong winds swept across Delhi on Tuesday, cleansing the city’s air and pushing its Air Quality Index (AQI) down to 73, a “satisfactory” level and the cleanest reading for October in over two years. The last time the capital breathed such air this month was on October 11, 2022, when the AQI stood at 66.
Data from the Central Pollution Control Board (CPCB) shows that this is the second “satisfactory” air day of the month, the previous one being October 3, when the AQI touched 88. Officials attributed the improvement to continuous rainfall and gusty south-easterly winds that helped disperse accumulated pollutants. The India Meteorological Department (IMD) reported wind speeds of up to 15 kmph, with gusts peaking at 46 kmph.
The downpour, driven by a Western Disturbance active over north Rajasthan and Haryana, drenched several parts of the Delhi-NCR region. Between Monday and Tuesday evening, the Palam weather station recorded 41.6 mm of rain, while Ridge received 37 mm, Pusa 22.5 mm, and Mayur Vihar 20 mm. Safdarjung, Delhi’s main observatory, logged a lighter 5.8 mm. In neighbouring Ghaziabad, rainfall reached 33.5 mm.
The impact was visible across the city, dark skies, poor visibility, and a noticeable drop in temperature. Visibility at Palam Airport plunged from 6,000 metres at 1:30 pm to 1,200 metres by 5 pm. The day’s maximum temperature fell to 29.8°C, about 4.4 degrees below the seasonal average, while the minimum settled at 21°C.
With the latest showers, Delhi’s rainfall for October has reached 75 mm, nearly five times the monthly normal of 15.1 mm. However, meteorologists say this could be the final spell of rain for the month. The IMD expects cloudy skies on Wednesday, followed by clear conditions later in the week, with temperatures hovering around 31°C during the day and 20°C at night.
Air quality is projected to stay between the “satisfactory” and “moderate” categories over the next couple of days. Meanwhile, satellite data from the Indian Agricultural Research Institute (IARI) recorded just five farm fires across six northern states on Tuesday, all in Madhya Pradesh, with none in Punjab, Haryana, Uttar Pradesh, Rajasthan, or Delhi. Since mid-September, a total of 215 stubble-burning incidents have been logged.
According to the Decision Support System for Air Quality Management, vehicular emissions continue to be the biggest source of Delhi’s pollution, contributing 15.3% to the overall load, followed by local sources in Gautam Buddha Nagar (6.8%) and Gurugram (6.76%).
Despite the brief relief, experts caution that Delhi’s air quality may deteriorate again as the post-monsoon season advances once winds slow down and farm fires in neighbouring states begin to rise.
