Mumbai sees its second wettest monsoon ever, beats last year's tally

Mumbai: Mumbai has witnessed its second wettest monsoon ever, beating last year’s seasonal rain tally.

After torrential downpour on Tuesday and Wednesday, rains eased on Thursday morning with a clear sky and sunshine after three days.

Mumbai received 395.1 mm rain over the last 48 hours, 53.7 mm more than what it generally receives throughout September.

From June 1 to September 24 morning, the Santacruz weather observatory, representative of the suburbs and Mumbai, recorded 3,679.8 mm rain. The quantum of rain last year was 3,670.4 mm. The highest all-time seasonal rainfall was during 1958 at 3,759.7mm, according to the India Meteorological Department (IMD). Thus, this year’s monsoon rain is the highest since 1959, or in 61 years.

Seasonal rain at Colaba weather station, representative of south Mumbai, was also the highest in 36 years with 3,198.7 from June 1 to September 4, 8.30am. Over the past 119 years (1901-2020), IMD data showed Colaba recorded its highest all-time seasonal rainfall in 1954 at 3,423.1 mm. In 1958 and 1983, Colaba had recorded 3,382.4 mm and 3,329.8 mm, making it a total of five such years (including 2020) in over a century that 3,000 mm rain was recorded.

“Mumbai and Maharashtra witnessed an exceptionally good monsoon this year with rain records in all months except June. Local weather factors helped lead to the highest monthly rain in July, the formation of five low pressure weather systems in August kept weather systems active along the west coast. Rain intensity is expected to gradually decline now as September ends,” said Mrutyunjay Mohapatra, director-general, IMD.

The past 48 hours saw extremely heavy rain lash the city, leaving many areas in waist deep water and traffic snarls. Between 8.30 am Wednesday and 8.30 am Thursday, 108.7 mm rain was recorded in the suburbs and 50.4 mm rain in south Mumbai. The previous 24 hours (8.30am Tuesday and 8.30am Wednesday) saw 286.4 mm rain in the suburbs, which was the heaviest rainfall witnessed this season, and 147.8mm rain in south Mumbai.

Location-wise rain over the past 24 hours showed several locations in Mumbai Metropolitan Region (MMR) received over 120 mm rain. Ram Mandir (near Goregaon) received maximum rain 138 mm followed by Lokhandwala 137.2 mm, Bandra 129.2mm, Worli 128mm, Thane 120.1mm, Navi Mumbai 134.2mm. The remaining areas across Mumbai received rain between 70-90 mm.

“Mumbai, Thane and Navi Mumbai received heavy to very heavy rain across isolated areas over the past 24 hours. More rain intensity was witnessed towards Thane and Navi Mumbai in the evening. Thursday started with a clear sky and possibility of a few showers towards evening,” said KS Hosalikar, deputy director general, western region, IMD.

The weather bureau has predicted the possibility of light to moderate rain for the remaining days of the month while independent meteorologists said the city will not receive any heavy rain spells as the season ends. However, monsoon withdrawal was not expected anytime soon. “Withdrawal could be delayed due to active La Niña conditions (a phenomenon when the western Pacific ocean warms up creating a low pressure near Australia pulling winds from the Indian Ocean strengthening equatorial dynamics keeping southwest monsoon circulation active) allowing rains to linger on for some more time over the west coast and central India,” said professor Sridhar Balasubramanian department of mechanical engineering and IDP Climate Studies, Indian Institute of Technology, Bombay.