The monsoon rolled into Calcutta on Wednesday over a week behind schedule but brought 39mm of rainfall that submerged several parts of the city.
The amount of rain was the most the city has received on monsoon Day One since 2009, the year Cyclone Aila forced its premature arrival on May 25. The rain gauge recorded 93.1mm that day.
Expect more showers, moderate to heavy, over the next four days, the forecast says.
The monsoon beat the mercury down to 32.1 degrees Celsius on Wednesday, a notch below normal, with clouds shutting out the sun for almost the entire day. The maximum temperature was almost four rungs lower than Tuesday’s 36 degrees Celsius.
The Celsius is likely to rise gradually but won’t touch the miserable 39s and 40s that hammered most of Bengal from March-end to a couple of days ago.
“The northern limit of the south-west monsoon covered most of Bengal on Tuesday, except some districts in the extreme west,” said G.C. Debnath, director of the India Meteorological Department in Calcutta.
The monsoon’s northern limit crossed Visakhapatnam, Bhubaneswar, Bankura and Darbhanga on Wednesday.
Moderate rainfall — up to 35.5mm a day — is expected on Thursday and Friday with the monsoon gaining strength.
“A cyclonic circulation over the Bay of Bengal that drifted towards Myanmar has shifted course back to the Bengal-Odisha coast. The weather system is pulling monsoon winds towards it. This is adding strength to the monsoon,” Debnath said.
Moderate rainfall is expected in Calcutta over the next two days because the Bay circulation is expected to move rapidly towards north Bengal after making landfall. But the coastal areas could get heavy rainfall on Thursday.
The monsoon brought in its wake the city’s yearly scourge: waterlogging.
Several areas in north Calcutta got submerged as it rained heavily in pockets since Wednesday morning on the back of moisture-laden south-westerly winds hitting Bengal.
Explaining the delayed arrival of the annual rain-bearer, experts said Cyclone Nanauk over the Arabian Sea slowed down the monsoon winds on the west coast. “But the cyclonic circulation active on the Bengal-Odisha coast is now acting as the catalyst, pulling the winds northward,” a weather scientist said.
Debnath said the rain distribution could remain skewed for some time since the weather has just entered its transitional phase. Rainfall will be typical of the season: summer-like thunderclouds working in tandem with layered, low-level monsoon clouds to bring long spells of drizzle rather than high-intensity downpour.
The Met office expects below-normal rainfall in June because of the monsoon’s late arrival.
Last year, the monsoon had arrived on schedule (June 8) in Calcutta but the cumulative rainfall from June 1 to June 17 was 141.5mm.
The aggregate of 159.3mm for the corresponding period this year is better, owing to a trough of low pressure over Bangladesh and adjoining areas that brought a few smart spells of thundershowers.