Late-November disaster affects millions across Southeast and South Asia, straining cross-border emergency capacity and blocking rescue access
A wave of monsoon-driven floods and landslides across Southeast and South Asia has killed more than 350 people and affected millions since late November 2025, with Indonesia and Thailand recording the highest death tolls. Authorities in six countries report rising casualties as rescue teams struggle to reach cut-off communities.
The deluge follows days of intense rainfall amplified by a rare tropical storm in the Malacca Strait and overlapping cyclone activity across the Bay of Bengal. Simultaneous emergencies in Indonesia, Thailand, Malaysia, Sri Lanka, India, and Vietnam are straining regional response capacity and exposing critical access bottlenecks that have slowed evacuations and relief operations.
Indonesia and Thailand bear the brunt
Indonesia has recorded at least 248 deaths, with more than 100 people missing and 500 injured after catastrophic flooding and landslides tore through Sumatra and parts of Java, according to the national disaster agency BNPB. West Sumatra, North Sumatra, and Aceh provinces saw bridges collapse and roads severed, cutting communications to remote valleys. At least 75,000 people have been displaced in West Sumatra alone, officials said November 29. Relief aircraft are airlifting supplies to Central Tapanuli, but saturated soils raise the risk of secondary landslides even as floodwaters begin to recede. BNPB has cautioned that the death toll will rise as access improves to isolated hamlets. Indonesia's landslide toll climbed steadily in previous days, underscoring the prolonged nature of the crisis.
Thailand reported at least 145 fatalities across eight southern provinces, with more than 3.6 million people affected. Songkhla province, including the regional hub of Hat Yai, was declared a disaster zone after the Royal Irrigation Department reported record rainfall of 630 millimeters in three days, with Hat Yai itself recording 335 millimeters in a single day—the highest in three centuries. Thai authorities deployed naval carrier and flotilla assets for relief, yet widespread power and communications outages in Hat Yai during peak flooding hampered evacuations. Thousands remain in temporary shelters, and officials warn that persistent inundation in low-lying areas will delay the return of displaced families. Thailand's military airlift has delivered tonnes of aid, but access constraints continue to slow the pace of relief.
Wider regional toll
Malaysia confirmed at least two deaths and more than 33,000 evacuees as of November 29, with Terengganu state recording the highest displacement numbers at 10,724 people and Kelantan facing significant flooding. Malaysian consular teams evacuated nationals stranded in flooded Thai hotels near the border, illustrating the cross-border ripple effect.
Sri Lanka's late-November rains triggered landslides and floods that killed at least 56 people and displaced thousands. India's Tamil Nadu and Puducherry states recorded at least 20 deaths after Cyclone Fengal brought heavy rains to coastal districts. In central Vietnam, severe floods and landslides earlier in November killed at least 90 people, with power outages affecting roughly 1.1 million customers at one point; exact national tallies vary as agencies continue to reconcile reports from remote areas.
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Meteorological drivers
Meteorologists attribute the widespread flooding to a convergence of weather systems rarely seen in tandem. A tropical storm formed in the narrow Malacca Strait between the Malay Peninsula and Sumatra—an unusual event that funneled moisture onto both coasts. Overlapping monsoon troughs and cyclones Robyn and Fengal intensified rainfall across the Bay of Bengal and Andaman Sea basins. The result was days of persistent, heavy rain across a 3,000-kilometer arc from Tamil Nadu to southern Thailand.
This sequence follows two rapid-succession typhoons that struck the Philippines earlier in November, killing at least 114 people and straining preparedness systems region-wide. Officials in multiple countries have described November 2025 as one of the most punishing storm seasons on record, with "unprecedented" rainfall totals recurring across basins that were already saturated.
What happens next
Casualty figures remain provisional and are expected to rise as rescue teams reach isolated valleys in Indonesia and southern Thailand. Waters are receding unevenly; some areas report floodwaters dropping, while others face renewed inundation from upstream releases and tidal surges. Transitions from rescue to recovery will likely begin in accessible zones within days, but priorities remain immediate: shelter, clean water, medical access, and restoring power and road links. Secondary landslides remain a near-term risk wherever soils stay saturated, particularly in Indonesia's mountainous provinces.
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