IMD Reports Fresh Low-Pressure Area Over Bay of Bengal, Forecasting Heavy Rains Across South Peninsula

The India Meteorological Department (IMD) has flagged a fresh low-pressure area brewing over the south-east Bay of Bengal, expected to form within the next two days or by Friday. The system is forecast to intensify into a well-marked low-pressure area by Saturday as it moves initially north-westwards. Global weather models suggest it could eventually develop into a depression or a cyclone, though there is currently no consensus on its final destination.

As of Wednesday morning, the developing Bay system presents two main weather scenarios: an immediate expansive spell of rain and thunderstorms over the South Peninsula, and a potentially powerful storm whose intensity and eventual path remain unsettled. The IMD has forecast isolated heavy rainfall over Tamil Nadu, Puducherry, and Karaikal, with another spell expected on Sunday and Monday. Kerala and Mahe could also experience isolated heavy rain on Monday, with the overall rain footprint expected to expand over the weekend.

Widespread rainfall is likely over Tamil Nadu, Puducherry, and Karaikal on Sunday, extending to Kerala and Mahe by Monday. Isolated to scattered rainfall is forecast over Tamil Nadu, Puducherry, and Karaikal over the four days beginning Wednesday and again on Monday. Kerala and Mahe are expected to see rain for five days starting Wednesday, while Lakshadweep anticipates rain for six days. Additionally, Coastal and South Interior Karnataka are likely to receive rain on Sunday and Monday, with coastal Andhra Pradesh, Yanam, and Rayalaseema seeing showers over three days beginning Saturday.

Tamil Nadu, Puducherry, and Karaikal are likely to experience thunderstorms, lightning, and gusty winds of 40-50 km/hr, gusting to 60 km/hr, on Wednesday, Thursday, Sunday, and Monday. Isolated thunderstorms and lightning are also forecast over these regions on Friday and Saturday; over Kerala, Mahe, and Lakshadweep on Wednesday and Thursday; and over Rayalaseema on Saturday.

The evolution and trajectory of the Bay system remain a key point of uncertainty. While the IMD has placed the system under watch for intensification into a well-marked low by Saturday, global tracking models are sharply divided over its destination. Some simulations point toward India's east coast, particularly Tamil Nadu and Andhra Pradesh, while others favor Sri Lanka. Additional projections indicate a track towards Bangladesh and Myanmar, with IMD's numerical models pointing toward a potential deep depression or cyclone turning east-north-eastwards across the Bay towards central Myanmar.

Meanwhile, Google DeepMind's machine-learning model, which assimilates hourly satellite and ground-station observations, assigns a 14 percent probability to the prospective storm surpassing very severe cyclone Arnab to become the strongest North Indian Ocean storm of the 2026 season. The model puts the probability of storm formation by Monday or Tuesday at 91 percent and estimates an 80 percent chance of it heading towards India's east coast within a week, by next Wednesday or Thursday. Alternative tracks include a 19 percent probability towards Bangladesh by next Thursday or Friday, 9 percent towards Myanmar, and a 6 percent chance of a westward diversion towards Sri Lanka.

"Unpredictable weather patterns and developing cyclonic systems in the Bay of Bengal carry significant operational and supply chain implications for businesses operating across southern and eastern coastal regions of India. Supply chain managers, logistics providers, and regional enterprises must closely monitor meteorological updates from agencies like the IMD to mitigate potential disruptions to transport, infrastructure, and local commerce during periods of heavy rainfall and severe storms." — Dr. Shishir Gupta, Founder & CEO, StartupLanes