mumbai

Updated: Apr 19, 2019 08:27 IST

Thursday was the city’s cleanest air day since beginning of the year, with an air quality index (AQI) of 71, which falls in the ‘satisfactory’ category. Mumbai’s air is expected to stay relatively pollution-free on Friday, too, with an expected AQI of 79 (satisfactory).

The System of Air Quality Weather Forecasting and Research (SAFAR), which records the data, categorises AQI levels for PM2.5 in the 0-50 range as good; 51-100 as satisfactory; 101-200 as moderate; 201-300 as poor; 301-400 as very poor and above 400 as severe.

Researchers from SAFAR said a combination of factors have led to clean air across north, northwest and western India.

“Earlier this week, thundershowers and dust storms raised air quality into the ‘severe’ category for the entire north and northwest India. But, with the sudden rainfall and high speed winds in the form of westerlies (north westerly winds), pollutants have dispersed,” said Gufran Beig, project director, SAFAR. “On Thursday, moisture levels were high in Mumbai, which reduced the pollutant carrying capacity in the air, and high speed sea breeze helped disperse the pollutants.”

Of the 10 Mumbai locations where AQI is monitored, Worli had the cleanest air at 39 (good) and Navi Mumbai was the most polluted at 123 (moderate).

AQI at the other locations was either in the ‘good’ or ‘satisfactory’ categories.

Meanwhile, temperatures across the city were near the normal mark for April, with the suburbs recording a maximum of 32.8 degrees Celsius and south Mumbai recording a 32.4 degrees Celsius. “The early setting in of sea breeze did not allow maximum temperatures to rise,” said an official from the India Meteorological Department (IMD), Mumbai.

A clear sky is expected during the day on Friday, with the evening and night expected to be partly cloudy.