Mumbai gets 46% of season’s average rain despite a 15-day delay in onset of monsoon
The weather bureau issued a forecast for intermittent rain in Mumbai and suburbs with occasional heavy spells for Friday and intermittent moderate showers for Saturday.Updated: Jul 05, 2019, 14:15 IST
Despite a fifteen-day delay in the onset of the southwest monsoon this year, the Santacruz weather station, representative of the suburbs and Mumbai, received 1,043.1mm rain till 5.30pm on Thursday, which is 46% of the entire season’s average rainfall. KJ Ramesh, general director, India Meteorological Department (IMD) said the city was likely to witness a pattern of extreme weather conditions owing to global warming.
Usually, monsoon arrives in Mumbai by June 10, but this year the India Meteorological Department (IMD) declared the onset on June 25. The average rainfall for monsoon season, from June 1 to September 30, at Santacruz is 2,272.3mm. Of the 1,043.1mm rainfall, 855.5mm was received between 8.30am on June 27 to 5.30pm on Thursday. Prior to this, only 187.6mm rain was reported since June 1, including pre-monsoon showers.
The season’s tally included the city’s highest 24-hour July rain — 375.2mm, falling under the ‘exceptionally heavy’ category — in 14 years and second highest in 45 years, recorded between 8.30am on July 1 and 8.30am on July 2. “These are the epochs of extreme weather events, which we are likely to witness much more under the current global warming or climate change scenario,” said Ramesh. “Like Mumbai, Gujarat had witnessed extremely heavy rain within a few days last year, equal to almost half the seasonal total. Recently, France recorded its highest all-time day temperature. Everywhere, unusual weather conditions are leading to a new manifestation of extreme weather events. While total number of rain days is reducing, higher quantum of rain is being recorded within short periods. This is likely to be the pattern now,” he said.
Ramesh also said whether extremely heavy rain will lead to flood-like situations depends on how well cities manage the drainage. “The changing pattern is a matter of concern. The entire west coast, including the Konkan coast, is likely to witness active monsoon conditions till the last week of July. We may not witness another exceptionally heavy rain situation like July 2 in Mumbai, but rainfall amount will range between 3cm to 7cm over 24 hours every day,” he said.
On Thursday, the suburbs recorded 22.6mm (moderate) rain between 8.30am and 5.30pm, while south Mumbai recorded 11.2mm (light) rain. The day temperature, both in the suburbs and south Mumbai, was at the normal mark while the night temperature in south Mumbai was 1.5 degree Celsius below normal at 24 degrees Celsius.
Moisture levels were very high with 95% humidity at south Mumbai and 92% in the suburbs.
The weather bureau issued a forecast for intermittent rain in the city and suburbs with occasional heavy spells for Friday and intermittent moderate showers for Saturday.
The district rainfall forecast stated that Mumbai is likely to receive heavy rain at isolated places on Sunday and Monday. “A cyclonic circulation (weather system) off the south Gujarat coast and another cyclonic circulation over northcentral Maharashtra adjoining south Gujarat combined with an east-west shear zone will enhance rain activity over Konkan till July 8,” an IMD official said.
Meanwhile, private weather forecasting agency Skymet withdrew its heavy rain alert, that it had issued earlier this week highlighting a risk of flooding in Mumbai between July 3 and 5, on Thursday. “Risk of serious flooding in Mumbai in the next few days has receded. Only light to moderate showers are expected in next few days, and the heavy rain alert is withdrawn,” said Jatin Singh, managing director, Skymet.