Kolkata waterlogged as red alert issued for South Bengal amid low-pressure threat
Synopsis
A deepening low-pressure system over the northwest Bay of Bengal has paralysed parts of Kolkata with waterlogging and pushed the RMC to issue a red alert for three South Bengal districts. With the system expected to become a depression by Monday and gale-force winds already lashing the coast, the next 48 hours are critical for Bengal.
Key Takeaways
The RMC Kolkata issued a red alert for Bankura , West Midnapore , and Jhargram on Monday and Tuesday, 17–18 August .
A low-pressure area over the northwest Bay of Bengal is expected to intensify into a depression by Monday .
Several areas of Kolkata are waterlogged; traffic movement has slowed significantly since Monday morning.
Gale-force winds of 40–50 km/h are blowing at sea; fishermen advised to stay off the north Bay of Bengal coast until Tuesday .
Rain is forecast to ease in South Bengal from Tuesday evening ; heavy rain continues across North Bengal through Tuesday.
Kolkata's minimum temperature on Monday was 25°C , 1.5 degrees below normal .
Heavy monsoon rain has left several areas of Kolkata waterlogged since Monday morning, 17 August, disrupting normal life and slowing traffic across the city, as the Regional Meteorological Centre (RMC) warned of continued heavy to very heavy rainfall across South Bengal districts for the next two days. The trigger is an active low-pressure area over the northwest Bay of Bengal that has intensified in recent hours and is expected to deepen into a depression by Monday.
Red Alert for Three Districts
The RMC Kolkata issued a red alert for heavy to very heavy rain in Bankura, West Midnapore, and Jhargram districts on Monday and Tuesday. The monsoon axis currently extends from Punjab through Haryana, Uttar Pradesh, and Jharkhand to the low-pressure system over the Bay of Bengal, funnelling sustained moisture into the region.
District-by-District Rainfall Forecast
On Monday, very heavy rainfall is expected in Howrah, Hooghly, Purulia, East Burdwan, West Burdwan, South 24 Parganas, and East Midnapore. Heavy rain is forecast for Kolkata, North 24 Parganas, Birbhum, Murshidabad, and Nadia.
On Tuesday, isolated heavy spells are likely in West Midnapore, Jhargram, Purulia, Bankura, West Burdwan, and Birbhum, with rain and thundershowers across the remaining South Bengal districts. Conditions are expected to ease from Tuesday evening onwards, and no further weather warning has been issued beyond that period.
Impact on Kolkata and Sea Conditions
Waterlogging across multiple Kolkata neighbourhoods has disrupted vehicular movement, with traffic crawling through inundated stretches since morning. The city recorded a minimum temperature of 25 degrees Celsius on Monday — 1.5 degrees below normal — while Sunday's maximum stood at 30 degrees Celsius, 1.9 degrees below normal, reflecting the pervasive cloud cover.
Gale-force winds of 40 to 50 kilometres per hour are blowing over the sea. Fishermen have been advised to stay off the north Bay of Bengal along the West Bengal and Odisha coasts until Tuesday.
North Bengal Also Under Rain Watch
Heavy rain is expected to continue across North Bengal through Tuesday as well. Jalpaiguri and Kalimpong are forecast to receive heavy rain on Monday, while Alipurduar and Darjeeling are in line for heavy spells on Tuesday. Scattered rain with thundershowers will persist in North Dinajpur, South Dinajpur, Malda, and Cooch Behar through Tuesday.
With the low-pressure system expected to intensify further, authorities and residents across Bengal are on watch as the weather pattern is set to remain volatile through at least mid-week.
Point of View
And each such event exposes the same unresolved gaps. The RMC's red alert and the prospect of a depression forming in the Bay of Bengal within hours raise the stakes considerably: if the system deepens faster than forecast, the response window for low-lying districts narrows sharply. Notably, the simultaneous strain on both South and North Bengal stretches state disaster management resources thin. Whether authorities have pre-positioned relief and evacuation capacity in the red-alert districts is the question mainstream coverage rarely asks until after the damage is done.
NationPress
17 Aug 2026
Frequently Asked Questions
Why is Kolkata experiencing heavy rain and waterlogging on 17 August?
An active low-pressure area over the northwest Bay of Bengal, combined with a monsoon axis stretching from Punjab to the Bay, is driving sustained heavy rainfall across South Bengal, including Kolkata. The system is expected to intensify into a depression by Monday, prolonging the rain through Tuesday.
Which districts are under red alert in West Bengal?
The Regional Meteorological Centre has issued a red alert for Bankura, West Midnapore, and Jhargram on Monday and Tuesday. Very heavy rain is also expected in Howrah, Hooghly, Purulia, East Burdwan, West Burdwan, South 24 Parganas, and East Midnapore on Monday.
When will the rain ease in South Bengal?
According to the RMC, rainfall is expected to decrease in South Bengal from Tuesday evening onwards. No further weather warning has been issued beyond that period.
Are fishermen in danger? What advisory has been issued?
Gale-force winds of 40 to 50 kilometres per hour are blowing over the sea. Fishermen have been advised not to venture into the north Bay of Bengal off the West Bengal and Odisha coasts until Tuesday.
Is North Bengal also affected by the current weather system?
Yes. Heavy rain is forecast to continue in North Bengal through Tuesday, with Jalpaiguri and Kalimpong expected to receive heavy spells on Monday, and Alipurduar and Darjeeling on Tuesday. Scattered rain with thundershowers will persist in North Dinajpur, South Dinajpur, Malda, and Cooch Behar.
