The India Meteorological Department office in Alipore has issued an alert for “enhanced rainfall activity” over south Bengal for three days starting Sunday morning.

According to the alert issued on Friday, heavy rain and wind are predicted for parts of Calcutta, Howrah, Hooghly, North 24-Parganas, South 24-Parganas and East and West Midnapore on Sunday and Monday. On Tuesday, the same pattern is expected mostly in East and West Midnapore, and South 24-Parganas.

The bulletin has reportedly been circulated on an emergency basis to boatmen and fishery associations in coastal south Bengal. Boatmen have been advised to return to shore latest by Saturday night.

“The low-pressure formation from the time of puja has shifted... and is predicted to deliver sustained wind and rain in south Bengal. It may paralyse normal life for three days,” said a Met official, explaining 7-11cm of rain is expected till Monday, following which cyclonic wind could persist for another day. He added gusty winds at a speed of 30-40kmph could start on Sunday.

In East Midnapore, constant drizzle in several towns started from Saturday afternoon. District officials set up a control room to monitor the weather and instructed civic volunteers at beaches to keep vigil on tourists and dissuade them from venturing out into the sea. “The Alipore Met office has given us the alert and we are instructing our personnel on the ground on the response,” said disaster management official Mrityunjay Haldar.

Fishery representatives are working to get all fishermen back on shore.

“We have sent the weather alert to registered fishermen, boat operators and related organisations,” said East Midnapore’s assistant director of fisheries (marine) Surajit Bag.

District officials added that efforts were underway to organise relief materials in anticipation of weather-related displacement.

According to the IMD alert, there is substantial possibility of waterlogging and crop damage, both of which have adversely affected coastal south Bengal on numerous occasions during the latter half of this year.

The same forecast of prolonged rain and squall-like weather is also predicted for parts of Bangladesh and Odisha.