Slight improvement in Delhi’s AQI as easterly winds bring respite from heat

The minimum temperature was recorded at 26°C on Thursday, a notch above normal, though it’s a tad below Wednesday’s minimum of 27.5°C, the highest so far this season

Delhi’s air quality improved to the ‘moderate’ category on Thursday, with moist easterly winds helping settle dust in the city air. The 24-hour average air quality index (AQI) was recorded at 185 (moderate) at 9am – a drop of 40 AQI points from Wednesday’s 4pm reading of 225 (poor), the Central Pollution Control Board (CPCB) data showed.

People walk past Kartavya Path on a hot summer day in New Delhi. (ANI Photo)

Forecasts by the India Meteorological Department (IMD) show strong easterly winds up to 30kmph are expected on Thursday as well, with chances of a western disturbance to begin influencing Delhi-NCR on Friday, possibly bringing light rain. It said that a spell of light rain is also possible on Saturday and Sunday.

The minimum temperature was recorded at 26°C on Thursday, a notch above normal, though it’s a tad below Wednesday’s minimum of 27.5°C, the highest so far this season.

“We began to see the impact of easterly winds from Wednesday itself, which not only brought a slight cooling effect, but also helped bring down dust,” said an IMD official, stating the wind direction should predominantly stay easterly or southeasterly till Sunday. Easterly winds blow towards Delhi from the Bay of Bengal, thus bringing moisture to the plains.

Delhi’s AQI had been over 200 for six consecutive days from May 3, making it the city’s worst spell of air quality in May since 2022, when nine such consecutive days were recorded. Dust is the primary source of pollution in the summer months, leading to a spike in PM10 concentration. In comparison, combustion sources are more dominant in the winter months and lead to a spike in PM2.5 concentration levels.

Meanwhile, the maximum temperature on Wednesday had come down to 38.2°C owing to winds, a day after a season high of 42°C was recorded. Forecast for Thursday shows the maximum should hover around 38°C, with chances of it rising to 40°C by Friday.