Triple cyclones batter Sri Lanka and South Asia

A rare cluster of three tropical cyclones across South Asia brought torrential rains and severe flooding to several countries.

Weather satellite data showed a specific pattern in the formation of this cluster of three cyclones, named Ditwah, Senyar, and Koto. It is unusual that these cyclones formed simultaneously over the Bay of Bengal, the Strait of Malacca, and the South China Sea.

Dr. Akshay Deoras, a meteorologist at the University of Reading in England, explained that while the simultaneous occurrence of Ditwah, Senyar, and Koto appears abnormal, their formation in the Bay of Bengal and the Western North Pacific during this time is not unprecedented.

However, foreign reports indicate this cluster is notable because all three systems formed under conditions not typically expected to generate powerful storms. Dr. Deoras emphasised that although the formation of such storms is not frequent, oceans warmed by climate change increasingly raise the chances of them becoming more intense. He further stressed that the primary danger currently stems from heavy rainfall and flooding.

• Ditwah (Southwest Bay of Bengal) is expected to weaken by November 30, but the thunderstorms it brings will likely move towards Southern India on that day.


• Koto (South China Sea) appears to have weakened and is expected to decrease in intensity after crossing Vietnam around December 3.


• Senyar, which was stuck between Malaysia and Indonesia, is reported to have dissipated, but it is still generating intense thunderstorms in that region.

This rare cluster of tropical cyclones brought intense monsoon thunderstorms to Sri Lanka, Indonesia, Malaysia, Thailand, and Vietnam.

The three storms caused catastrophic floods, landslides, and river overflows, resulting in numerous deaths across the affected countries, with millions forced to abandon their homes.

Data calculated by combining satellite, radar, and ground measurements indicated rainfall values exceeding 53–100 mm per hour in many affected regions. Some of the worst-hit locations, especially in Sri Lanka, experienced rainfall exceeding 300 mm per hour over the past 48 hours.

In Sri Lanka, 123 fatalities are currently reported, with hundreds of thousands of people affected.