Mumbai witnessed light showers with high wind speed through the day on Wednesday under the influence of the tropical cyclone Vayu.

The air quality index (AQI) on Wednesday was recorded at 43, falling under the good category, making it the cleanest air day so far this year, said researchers from the System of Air Quality Weather Forecasting and Research (SAFAR).

AQI levels last year during April were at its lowest since AQI monitoring began in Mumbai at 18 (good).

“The increase in moisture allowed the carrying capacity of pollutants in Mumbai’s air to increase, which was further dispersed by high-speed winds leading to good air quality,” said Gufran Beig, project director, SAFAR. “Now, air pollution is likely to increase as the cyclone has moved away while dust from nearby areas will begin accumulating.”

According to the weather bureau, the cyclone brushed past the Mumbai coast, around 2.30pm at a distance of 250km in the Arabian Sea, paving way for gusty winds at a maximum speed of 20 kmph. Between 8.30am and 8.30pm Wednesday, the suburbs recorded 14.2mm, while south Mumbai recorded 16.8mm rain. The quantum of rainfall fell under the light category for the suburbs, but moderate category for south Mumbai. However, during the same time, Ratnagiri recorded 47mm rain, which was the highest along the Konkan coast. According to the weather department’s classification, 15.6mm to 64.4mm of rainfall is considered ‘moderate’, 64.5mm to 115.5mm ‘heavy’, 115.6mm to 204.4mm ‘very heavy’ and more than 204.5mm is ‘extreme’.

“The severe cyclonic storm that moved past Mumbai did not have any adverse effect apart from light rain and gusty winds. Rainfall over Mumbai is expected to reduce from Thursday onwards until the onset of the southwest monsoon. However, Vayu has now intensified into a very severe cyclonic storm and it is around 200km off the coast of Gujarat (Veraval),” said KS Hosalikar, deputy director general, western region, India Meteorological Department (IMD), adding that the cyclone is likely to lead to an adverse impact over the Gujarat coast by Thursday early morning.

Meanwhile, day temperatures in the city were close to the normal mark, while the night temperatures were a degree Celsius below normal.

The city can expect generally cloudy skies with chances of moderate rain on Thursday and Friday.

First Published: Jun 13, 2019 10:02 IST