Heavy rain lashed the city for the second consecutive day on Wednesday, with some areas recording over 100mm in just a few hours.

The weather office has issued a rain alert for the next two days.

The downpour led to waterlogging in several stretches. “The lock gates of the Hooghly were open when the rain was at its peak. Otherwise, things would have been worse,” said an official of the Calcutta Municipal Corporation.

The rain was triggered by a cyclonic circulation over the north Bay of Bengal, which had led to the rain on Tuesday as well, and the position of the monsoon trough. The trough passes over Santiniketan and Diamond Harbour and merges with the circulation, said a Met official.

Central Avenue around 4pm on Wednesday. Pradip Sanyal

The city is likely to get more rain over the next two days, he said. “The system is unlikely to intensify but is likely to persist till Friday. It is close to the Bengal coast and will have an impact for the next 48 hours,” the official said.

On Wednesday, rain-bearing clouds travelled from east to west and, aided by strong monsoon currents, brought rain to Calcutta.

The city experienced the bulk of the rainfall from 10am to 4pm, in multiple spells. In many places, a drizzle persisted till late evening.

From 8.30am to 8.30pm on Wednesday, the Met office recorded around 80mm of rain each at Dum Dum and Salt Lake observatories. Alipore recorded around 25mm.

Ultadanga was the wettest area in the city, having received over 110mm of rain between 11am and 4pm, according to CMC figures. Maniktala got around 85mm, Topsia 78mm and Thanthania got 75mm.

In comparison, Kalighat got 35mm and Jodhpur Park 45mm. Areas along the EM Bypass received heavy rainfall, too. CMC’s Dhapa pumping station received 90 mm of rainfall.

In Met parlance, 60-120mm of rain in 24 hours qualifies as heavy.

Sukeas Street, Amherst Street, Muktaram Babu Street, College Street and BB Ganguly Street had ankle deep water by the afternoon. Around 3pm, parts of Central Avenue, Shakespeare Sarani and Camac Street were flooded, too.

Traffic was stalled as busy thoroughfares across the city went under the water.

“The water receded from most areas in the evening. Only a few areas, like Thanthania, Muktaram Babu Street, some parts of Central Avenue and College Street were waterlogged even after 6pm,” said an official of the CMC.