Kolkata has enjoyed a dry, pleasant stretch after the Puja crowds, but the sky is about to change its mood. A low pressure area has formed over the south-east Bay of Bengal, and the India Meteorological Department (IMD) says it could grow into a cyclonic storm by Monday, October 26. If it does, it will be called Arnab, a name proposed by Bangladesh that means “ocean” in Bengali.
The storm is expected to head towards the Andhra Pradesh and Odisha coasts, so Kolkata is not in its direct path. Even so, the city and the rest of south Bengal should expect a spell of rain, gusty winds and cooler days from the middle of next week. This guide explains what has been forecast, which districts are most exposed and how to plan around it.
What the IMD Has Said So Far
According to reports published on October 23 and 24, the system formed on Friday. The expected progression is simple: a depression on Saturday, a deep depression on Sunday, and a cyclonic storm over the west-central Bay of Bengal on Monday. After that it is likely to move west-north-west towards north Andhra Pradesh and south Odisha.
The exact track and the point where it may cross the coast have not been fixed yet. Forecasts for a system that is still forming can shift, so treat every date below as a current estimate and not a promise.
What to Expect in Kolkata and South Bengal
South Bengal is expected to stay largely dry until Monday. The change begins from Tuesday, when light to moderate rain is likely in Kolkata, Howrah, North and South 24 Parganas, Purba and Paschim Medinipur and Jhargram. Conditions look wetter on Wednesday, October 28, with heavy rain forecast at isolated places in South 24 Parganas, the two Medinipur districts and Jhargram. Reports mention figures in the range of 70 to 110 mm for the heaviest pockets.
Heavy rain is also flagged for Purulia and Bankura. Thunderstorms with gusts of up to 40 km/h are expected across south Bengal from October 28, and one report mentions squally winds of 40 to 50 km/h along and off the Bengal coast from Tuesday. Daytime temperatures in southern districts may fall by two to three degrees Celsius, which will make afternoons noticeably more comfortable.
For Kolkata itself, the forecast so far points to thunderstorms and rain rather than anything severe. That said, the city’s old drainage is known to struggle when a heavy downpour arrives in a short window, so low-lying areas deserve some attention.
Fishermen and Coastal Districts
The IMD has advised fishermen not to venture into the sea. Reports differ slightly on the start date, with one citing October 26 and another October 27, so anyone working along the coast should simply stay ashore from the weekend and follow the latest district advisories. Coastal belts of South 24 Parganas and Purba Medinipur, including the Sundarbans fringe and the Digha side, are the places most likely to see rough water and strong winds.
Why This Matters Locally
The timing is awkward. Late October is when many families travel after Durga Puja, shops prepare for Kali Puja and Diwali, and Chhath preparations begin on the ghats. Rain and wind in the middle of that calendar can affect pandal and stall set-ups, outdoor markets, ferry services on the Hooghly and road traffic on waterlogging-prone stretches.
It also follows a pattern the city has seen before. We tracked a similar Bay of Bengal system just before Puja in our earlier report on the fresh low pressure watched ahead of Durga Puja. That one did not reach cyclonic-storm strength and crossed the coast as a deep depression, bringing heavy rain to Andhra Pradesh and Odisha. The current system may behave differently, which is why the next few updates matter.
Practical Tips for Kolkata Residents
- Check the IMD Kolkata bulletin each morning from Sunday, because the track and intensity can change quickly.
- Carry an umbrella or raincoat from Tuesday onwards, and avoid parking in known waterlogging spots such as low-lying pockets near canals and underpasses.
- If you are planning an outdoor Kali Puja, Diwali or Chhath arrangement for October 28, keep tarpaulin and a covered backup space ready.
- Keep phones and power banks charged in case of power cuts during thunderstorms, and stay away from loose hoardings, damaged wires and large trees during gusty spells.
- If you are travelling to Digha, Mandarmani or the Sundarbans, check ferry and road status before leaving and consider postponing coastal trips.
- Do not wade through standing water near exposed electric cables.
Frequently Asked Questions
Will Cyclone Arnab hit Kolkata?
Current forecasts do not point to a direct hit. The system is expected to move towards the Andhra Pradesh and Odisha coasts. Kolkata and south Bengal are likely to feel the outer effects in the form of rain, thunderstorms and gusty winds from about October 27 and 28.
When will it start raining in Kolkata?
Light to moderate rain is expected from Tuesday, October 27, with the heavier spell forecast around Wednesday, October 28. Until Monday, the weather should stay mostly dry.
Is it confirmed that the system will become a cyclone?
No. The IMD says it is likely to intensify into a cyclonic storm by October 26, but it has not been confirmed. It may stay a depression or deep depression, and the name Arnab is used only if it reaches cyclonic-storm strength.
Which districts of Bengal may get heavy rain?
South 24 Parganas, Purba Medinipur, Paschim Medinipur, Jhargram, Purulia and Bankura have been named in the forecasts.
Will the rain affect Kali Puja and Diwali plans?
It could, mainly around October 28. Plan for a covered backup and watch the latest forecast closer to the day.
The Bottom Line
For Kolkata, this is a story about a wet and breezy midweek, not an emergency. The cyclone itself is expected to make landfall far to the south-west, but its outer bands can still bring thunderstorms, cooler afternoons and waterlogging to parts of the city and heavy rain to coastal Bengal. Watch the IMD updates over the weekend, keep festival and travel plans flexible for October 27 and 28, and stay out of the water near the coast.
Sources: India Meteorological Department forecasts as reported by The Federal (October 23, 2026), Millennium Post (October 24, 2026) and India TV News (October 23, 2026). This article was written independently and the forecast may change as the system develops.
Featured image: People holding umbrellas and walking on a wet road, photo by matthew smith on Unsplash.
