With 58.3mm rainfall within 12 hours, Mumbai has surpassed the 3,000-mm mark for the season on Friday evening.
From June 1 to 8.30pm on August 28, Santacruz weather observatory, representative of the suburbs and Mumbai, recorded 3,011.4mm rain. During the same period, Colaba weather station, representative of south Mumbai, recorded 2,772.5mm rain.
The India Meteorological Department (IMD) has issued a yellow alert (heavy rain at isolated areas) between Friday night and Saturday morning and through the day on Saturday for Mumbai and Thane.
Last year, Mumbai had surpassed the 3,000-mm mark on September 5 and had recorded 3,695.6mm rain throughout the season (June 25 to October 14), which was the second wettest all-time monsoon for the city. The highest rainfall for the season was recorded in 1958 at 3,759.7mm, as per data from the India Meteorological Department (IMD). In 2018, the total rainfall for the season was 2,243.4mm rain while it was 3,029.9mm in 2017.
This year monsoon onset was declared on June 14. The southwest monsoon generally spans over four months (June to September), but withdrawal is generally declared by the second week of October. The new official withdrawal date for Mumbai is October 8, as declared by IMD in June this year.
The city surpassed its seasonal rain target of 2,260.4mm on August 5 and annual average rain target of 2,514mm on August 9. This season, Mumbai has witnessed the lowest June rain (395mm) in five years, highest July rain (1,502.7mm) since records began being collated in 1944, and 1,113.8mm rain in August, highest since 1983.
On Friday, as opposed to light to moderate rain prediction by the weather bureau, the suburbs recorded 58.3mm rain while south Mumbai recorded 64.4mm rain between 8.30am and 8.30pm. IMD classifies 15.6-64.4mm as moderate and 64.5-115.5mm rain as heavy. The city witnessed light to moderate showers with intermittent intense spells towards the eastern suburbs and surrounding regions of the Mumbai Metropolitan Region (MMR) than south Mumbai and central suburbs.
KS Hosalikar, deputy director general, western region, IMD, said, “Monsoon conditions are active across coastal Maharashtra and closer to central India under the influence of a well-marked low-pressure weather system located over north Chhattisgarh adjoining east Madhya Pradesh. It is likely for this system to move west-northwest over south Uttar Pradesh over the next 48 hours allowing rain intensity to be similar to what is being observed over Mumbai on Friday. Additionally, convergence due to strong lower level southwesterly winds from the Arabian Sea and easterly winds from Bay of Bengal during this period would enhance rain activity.”
Rain intensity was more over the past 12 hours (8am to 8pm on Friday) and location-wise rain showed Chembur recorded highest rain at 104mm followed by Kalyan 83.5mm, Mumbra 82.5mm, Navi Mumbai 80.2mm, Dombivli 79mm, Bhayandar 75mm, Bandra 62mm, BKC 53.6mm, Dahisar 51mm, Worli 43.4mm, and Mazagaon 26 mm. “Satellite and radar images indicated intense cloud formation over the north Konkan coast. Dense cloud patches were observed towards the eastern suburbs, Chembur rain figure is indicative of that,” said Hosalikar.
IMD updated its district-wise rain forecast at 1pm with a yellow alert (heavy rain at isolated areas) for the rest of Friday and for Saturday for Mumbai and Thane. An orange alert (heavy to very rain) has been issued for Palghar and Raigad for Saturday. Heavy rain warnings have also been issued for Pune, Kolhapur, and the entire Vidarbha sub division.
Independent meteorologists had predicted that MMR would witness an increase in rain from August 28 in response to the low-pressure system over central India. “There isn’t any severe weather potential since only moderate rain will continue. September will begin on a drier note and there are indications of subdued rain continuing during the first week. In fact, below average rainfall activity is possible in the first fortnight of September,” said Akshay Deoras, independent meteorologist and PhD researcher at the University of Reading, United Kingdom.
The city and suburbs can expect cloudy conditions with moderate to heavy rain on Saturday. The Indian National Centre for Ocean Information Services (INCOIS) issued a high wind alert for the west coast, especially along Gujarat, for winds gusting to 45-55kmph and fishing community were advised not venture out to sea.