Delhi recorded its cleanest May in five years, with improving weather conditions helping bring pollution levels down significantly. On Saturday, the city's Air Quality Index (AQI) dropped to 85, placing it in the "satisfactory" category and marking the cleanest air day recorded in more than seven months. The AQI was last lower on October 8, 2025, when it stood at 80. The latest reading also capped a month that saw better air quality than recent years, making May 2026 the cleanest May the national capital has experienced since 2021.
Rain and gusty winds bring relief
Residents received another break from the intense summer heat as strong winds and scattered afternoon showers kept temperatures under control for a second consecutive day.
According to the India Meteorological Department (IMD), the maximum temperature settled at 37.1 degrees Celsius, which was more than three degrees below the seasonal average. The minimum temperature was recorded at 24.6 degrees Celsius.
Weather experts said the combination of rainfall and strong winds helped disperse pollutants, leading to a noticeable improvement in air quality across the city.
4th ‘satisfactory’ AQI day this month
Saturday marked the fourth day in May when Delhi's air quality remained in the satisfactory category. Earlier in the month, the city recorded AQI levels of 88, 86 and 100 on May 4, May 5 and May 8 respectively. Under the Central Pollution Control Board's classification, an AQI between 51 and 100 falls in the satisfactory category, indicating relatively cleaner air and lower health risks for residents.
The changing weather prompted the IMD to issue alerts across several parts of Delhi and the National Capital Region.
A red alert was issued on Saturday afternoon for parts of north, northwest, west, central and northeast Delhi, warning of thunderstorms accompanied by strong winds reaching speeds of up to 80 kmph. Several areas witnessed light rainfall, with Mayur Vihar recording the highest precipitation at 4 mm. Lodhi Road received 3.8 mm of rain, while Safdarjung recorded 0.9 mm.
The weather also disrupted air traffic, forcing three flights headed for Delhi to be diverted to Lucknow.
While the cooler weather has brought temporary relief, forecasters expect temperatures to gradually rise again from next week. The maximum temperature is likely to touch 40-42 degrees Celsius by June 4 as skies begin to clear. However, meteorologists expect occasional thunderstorms and pre-monsoon activity to continue through June, providing intermittent breaks from the heat.
A different picture from last year
The cleaner air comes in sharp contrast to last year, when Delhi witnessed one of its hottest Mays on record. In 2024, the city recorded an average temperature of 41.7 degrees Celsius and experienced six consecutive heatwave days at the end of the month.
This year, Delhi officially recorded only one heatwave day, although temperatures remained above 40 degrees Celsius for nearly two weeks during the second half of May.
