Delhi sees cleanest February day in 2 years

The India Meteorological Department (IMD) has forecast strong surface winds of 20-30 km/hr till Saturday

Delhi residents experienced their cleanest air day in four months and the cleanest February day in two years, as strong winds in the early hours of Thursday swept away pollutants, leaving the city with uncharacteristically clear blue skies.

At Lodhi Garden on Thursday morning. (Vipin Kumar/HT Photo)

The 24-hour average air quality index (AQI) stood at 134 (moderate) at 4 pm Thursday, when the Central Pollution Control Board (CPCB) releases its national daily bulletin.

This made it the cleanest day since October 10, when the AQI was 132. It was also the best air quality in February since February 14, 2023, when the AQI was also 132.

In the last 48 hours, Delhi’s air quality improved by over 150 points, dropping from 293 (poor) on Tuesday to 212 (poor) on Wednesday. Forecasts predict winds up to 25 km/hr on Saturday, likely keeping the AQI in the “moderate” range.

CPCB classifies AQI between 0 and 50 as “good”, between 51 and 100 as “satisfactory”, between 101 and 200 as “moderate”, between 201 and 300 as “poor”, between 301 and 400 as “very poor”, and over 400 as “severe”.

“Since Wednesday, we have been seeing good wind speed in the city. These consistent winds are raising dust, but mostly helping pollutants disperse. Before that, on both Monday and Tuesday, winds were mostly calm and that led to AQI deteriorating rapidly,” said Mahesh Palawat, vice president at Skymet.

Forecasts by the Centre’s Early Warning System for Delhi (EWS) shows the AQI should remain in the “moderate” category till Saturday. A dip in wind speed is likely from Sunday again.

“The AQI is likely to be in ‘poor’ on February 16. In the subsequent six days, the AQI is likely to remain ‘poor’,” said the EWS in its daily bulletin.

Mercury dips due to strong winds

The strong winds also led to a drop in Delhi’s maximum temperature, which fell to 24.8°C on Thursday from 29.7°C on Tuesday, the year’s warmest day so far.

While Delhi’s maximum and minimum is recorded at the Safdarjung observatory, other locations recorded an even cooler day. The lowest maximum across the city was 23°C at west Delhi’s Pusa.

The India Meteorological Department (IMD) forecasts wind speeds of 25-35 km/hr on Friday, with daytime temperatures between 24-26°C. Nights are getting warmer, with the minimum temperature rising to 12°C on Thursday, two degrees above normal. It is expected to range between 9-12°C over the next two days.