A weather system over the Bay of Bengal is gathering strength and is likely to intensify into a cyclonic storm by the morning of October 26, the India Meteorological Department has said, putting the coasts of Andhra Pradesh and Odisha on alert for heavy rain, squally winds and rough seas in the days ahead.
According to the IMD's latest update, issued on the morning of Saturday, October 24, a well-marked low-pressure area lay over the east-central Bay of Bengal at 5:30 am. The system is expected to move west-northwestwards and intensify into a depression on Saturday, deepen into a deep depression on Sunday, and become a cyclonic storm over the west-central Bay of Bengal by Monday morning.
It is then likely to continue on the same track and approach the west-central Bay of Bengal near the Andhra Pradesh coast around the morning of Wednesday, October 28.
The forecast has set off a chain of warnings and preparations across eastern India. IMD Director General Mrutyunjay Mohapatra, speaking to reporters, laid out the step-by-step intensification timeline and urged all operational authorities and maritime sectors to activate emergency protocols.
He said the most important thing was for all marine activities — fishing boats, shipping, onshore and offshore industries and port authorities — to take preparatory action against the impending cyclone.
The rainfall forecast is the most immediate concern for coastal districts. Coastal Odisha is likely to receive heavy to very heavy rainfall at a few places on October 27, while isolated heavy rainfall is expected over coastal West Bengal the same day. On October 28, north Andhra Pradesh and Odisha are likely to experience heavy to very heavy rainfall at a few places, with extremely heavy rainfall exceeding 20 centimetres in 24 hours possible in parts of the region.
Isolated heavy to very heavy rainfall is also likely over West Bengal on October 28, and Chhattisgarh, Jharkhand and Bihar may receive isolated heavy rainfall on October 28 and 29.
Winds over the sea are already picking up. Under the system's influence, wind speeds of about 35 to 45 kilometres per hour, gusting to 55 kilometres per hour, were reported over the east-central and adjoining southeast Bay of Bengal. As the system strengthens, winds and sea conditions are expected to worsen considerably, and fishermen have been advised to return to shore and not venture into the sea.
State administrations have begun to move. Odisha has cancelled staff leave and kept teams of the National Disaster Response Force and the Odisha Disaster Rapid Action Force on standby, while Andhra Pradesh authorities have readied shelters and warned fishermen to return to shore. Naga Ratna, head of the Amaravati Meteorological Centre in Andhra Pradesh, said the weather system was likely to cross the coast in the early hours of October 28 and move towards Odisha the next day.
The IMD's Bhubaneswar centre has similarly said the system is likely to cross the southern Odisha and northern Andhra Pradesh coast by October 28.
If the system does become a cyclonic storm, it will be named Arnab, the next name on the regional tropical cyclone naming list maintained by the World Meteorological Organization and the IMD. The name Arnab, which means "ocean" in Bengali, was contributed by Bangladesh.
Some forecast models suggest the system could reach at least severe cyclonic storm strength, with peak winds near 145 kilometres per hour, very rough seas and a storm surge of one to two metres in vulnerable coastal pockets, though forecasters stress that there is considerable uncertainty about the exact track and final intensity.
That uncertainty is worth emphasising. A weather system last month also triggered a cyclone watch but ended up not intensifying into a cyclonic storm; it crossed the Andhra Pradesh-Odisha coast as a deep depression and still brought heavy rain.
Forecasters say changes in wind shear or fresh observations over the next 48 to 72 hours could shift the impacts and timing of the current system, and residents are advised to follow IMD bulletins and local evacuation orders rather than relying on any single forecast.
The Bay of Bengal is no stranger to October cyclones. The post-monsoon months of October and November are the peak season for cyclonic storms in the basin, when warm sea surface temperatures and favourable atmospheric conditions allow low-pressure systems to spin up quickly.
Odisha and Andhra Pradesh, with their long, low-lying coastlines, have borne the brunt of many of the most destructive storms in Indian history, and both states have invested heavily in early warning systems, cyclone shelters and evacuation drills in recent decades.
Those investments have dramatically reduced loss of life in recent storms, but the risk to property, crops and infrastructure remains high, particularly when extremely heavy rainfall coincides with storm surge in coastal districts.
For coastal communities, the coming days will be a test of that preparedness. Farmers in the coastal districts face the prospect of damage to standing crops; fishing communities face days without income while boats stay ashore; and urban areas face the risk of waterlogging if extremely heavy rain falls in a short period. The IMD has said it is monitoring the system continuously and will issue further updates as the situation evolves.
The advisory for the public is straightforward: stay informed through official IMD bulletins, avoid venturing into the sea, secure loose objects and livestock, and be ready to move to shelters if local authorities issue evacuation orders. The system is still days from landfall, and its final strength and track are not yet settled — but the direction of travel is clear, and the coasts of Andhra Pradesh and Odisha should prepare for a wet and windy week.
As the system moves west-northwestwards over the coming days, each fresh IMD bulletin will refine the picture: whether it becomes a cyclonic storm on schedule on Monday morning, how strong it gets, and precisely where it comes ashore. For now, the message from the weather office is one of watchful urgency — a storm is brewing in the Bay, and the eastern seaboard has several days to get ready.
(Reporting based on DD India, The Hindu and Hindustan Times.)