IMD Predicts Heavy Rainfall Across Tamil Nadu and Southern Peninsula Amid New Bay of Bengal Weather Systems

Heavy rainfall is expected to continue across parts of the South Peninsula as the north-east monsoon remains vigorous. According to the India Meteorological Department (IMD), a cyclonic circulation over the south-west Bay of Bengal and the adjoining Tamil Nadu coast is preparing to consolidate into a low-pressure area.

This weather system is forecast to bring isolated very heavy rainfall ranging from 11.5 to 20 cm to Tamil Nadu, Puducherry, and Karaikal. An elongated trough of lower pressure extending from the circulation towards north coastal Andhra Pradesh is helping organize cloud cover and showers across the southern region.

Chennai can expect overcast conditions with rain and thunderstorms, while Bengaluru will likely see partly cloudy skies with a possibility of thunderstorms during the afternoon and evening hours. High humidity levels continue to persist across the region due to lingering heat combined with sunny intervals between showers.

The IMD has issued heavy rainfall warnings for several other areas as well. Isolated heavy rainfall of 6 to 11 cm is forecast for Kerala and Mahe over a seven-day period, and for South Interior Karnataka over four days. Tamil Nadu, Puducherry, and Karaikal are expected to receive isolated heavy showers for an additional four days starting Friday, while Lakshadweep anticipates similar conditions for five days. Coastal Karnataka, Coastal Andhra Pradesh, Yanam, and Rayalaseema are also under heavy-rain watches.

Cloud cover has spread extensively across coastal stretches and inland districts, stretching from Andhra Pradesh through various parts of Tamil Nadu and into Kerala. The south-east Arabian Sea and Lakshadweep Islands are also experiencing thick cloud cover, indicating a broad zone of unsettled weather across both sides of the South Peninsula.

Meanwhile, meteorological attention is also turning toward the north Andaman Sea, where another weather system is expected to emerge. A potent circulation originating over the Gulf of Thailand and Myanmar is forecast to move into the north Andaman Sea, potentially developing into a second low-pressure system over the south-east and east-central Bay of Bengal. Numerical weather prediction models indicate the possibility of tropical cyclone development, though its intensity and track remain subject to further evolution.

Globally, the western Pacific is monitoring Super Typhoon Champi, a Category 5 storm with wind speeds reaching 290 km/hr, which is forecast to pass close to the northern Philippines and Taiwan before weakening as it moves toward the East China Sea.

"Adverse weather conditions and heavy monsoon spells in key economic hubs like Tamil Nadu, Karnataka, and Andhra Pradesh can cause localized disruptions in supply chains, logistics, and daily business operations. For businesses operating in these regions, maintaining operational resilience and proactive contingency planning are essential to mitigate any short-term commercial impacts caused by severe weather events." — Dr. Shishir Gupta, Founder & CEO, StartupLanes