South Bengal, including Kolkata and its adjoining districts, is likely to face unsettled weather and periods of heavy rainfall over the next three to four days as a low-pressure system develops over the north Andaman Sea, weather officials said.
The system began as an upper-air cyclonic circulation over north Thailand before emerging over the north Andaman Sea. A low-pressure area is likely to form over the same region and gradually intensify while moving towards the south Odisha–north Andhra Pradesh coasts over the following three to four days, according to an official quoted in the report.
Weather scientists have indicated that the system could intensify into a depression at a later stage. While the primary impact is expected over the neighbouring coastal region, West Bengal, particularly the coastal districts of South Bengal, may experience its secondary effects.
Kolkata and nearby districts have already received heavy rain for the second consecutive day. The Regional Meteorological Centre attributed the rainfall over the past two days to a trough line extending from Sikkim to the North Bay of Bengal across Bangladesh.
The weather office has issued a yellow warning for thunderstorms, lightning and gusty winds in parts of South Bengal. The developing system is expected to keep conditions unsettled across several districts during the coming days, with residents in coastal and adjoining areas likely to experience spells of heavy rain accompanied by thunderstorms and strong winds.
The warning has direct implications for the way cities and districts manage vulnerable locations during intense rain. Low-lying areas remain particularly exposed to water accumulation and disruption when heavy rainfall coincides with gusty winds and thunderstorms. The report said authorities had been advised to remain alert, especially in vulnerable and low-lying areas.
The system also poses risks for people working at sea. Fishermen and others involved in marine activities have been advised to remain cautious as conditions over the sea could deteriorate under its influence.
For Kolkata and its adjoining urban areas, the immediate concern is the continuation of wet and unstable weather after two days of heavy rain. The report does not specify the expected rainfall totals or identify particular city roads, neighbourhoods or civic facilities likely to be affected.
The Regional Meteorological Centre is monitoring the movement and intensification of the low-pressure area. Further warnings may be issued depending on how the system develops and tracks towards the coast.
