Rain impact: Max-min difference down to 1°C

Kolkata: The city received consistent overnight rain that continued through the day on Saturday, pulling the maximum temperature down to 26.5°C, just a degree more than the day’s minimum temperature of 25.2°C. Some parts of the city received heavier spells and were left waterlogged after repeated spells, though the water receded by late afternoon. Kolkata received 53.4 mm rain on Saturday.
A deep depression over Gangetic Bengal and adjoining Bangladesh, that has triggered the showers, moved west-southwestwards at a speed of 18 kmph on Saturday morning, said the Met office.It is likely to trigger more heavy rain in Kolkata on Sunday, including one or two intense spells, with wind speed reaching 40-50 km/hr, gusting to 60 km/hr. But the frequency and the intensity of the showers could lessen.

A bulletin issued by the Regional Meteorological Centre, Alipore, said the depression lay 160 km east-southeast of Bankura on Saturday afternoon. “It is likely to continue to move west-northwestwards across Jharkhand, north Chhattisgarh and Madhya Pradesh as a depression during the subsequent 48 hours,” said the bulletin.
It added that the monsoon trough now passes through the centre of deep depression over Gangetic Bengal and Bangladesh and ‘thence south-southeastwards to northeast Bay of Bengal’.
The cloud cover blocked out sun rays and pulled the temperature down, said RMC weather scientist HR Biswas. “We expect spells of drizzle to continue on Sunday and the cloud cover will persist. The maximum temperature may rise by a couple of degrees but it will remain cool and moist. The depression is a big system and is moving slowly so the impact will persist for more than a day,” said Biswas.
He added that the impact of the depression will wane off by Monday.
The rain started late on Friday evening with a sharp spell at around 9.30 pm. It stopped after about 45 minutes only to resume with a greater intensity at around 2 am on Saturday.
The Kolkata Municipal Corporation sewerage and drainage department has alerted the executive engineers in-charge of the city’s major drainage pumping stations to keep all heavy-duty pumps operational to flush out storm water from the waterlogged streets in the event of a downpour. Similarly, the KMC drainage department has kept portable pumps ready for the city’s low lying and waterlogging-prone areas particularly in added areas like parts of Behala, Garden Reach, Tollygunge and neighbourhoods located off EM Bypass where a drainage upgrade work is in progress.
The KMC has kept a sewer desilting gang ready for cleaning the clogged drains in the event of heavy rain.