Looking at the weather map on his computer, he sees three tropical storms forming simultaneously. throughout Asia In late November, climate scientist Fredolin Tanggang's first thoughts turned to the 2004 disaster film The Day After Tomorrow.
The film, in which three powerful storms plunge the Earth into a new ice age, goes beyond reality. But there was something about the formation of those weather systems swirling on his screen that made Tangan sit up.
These weren't the worst storms this year. But they were “unusual,” said Tangan, an emeritus professor at the National University of Malaysia.
One of them was seething near the equator off the coast of Indonesia, an area where storms rarely take shape because the planet's rotation there is too weak to cause them to exist. Another tracked areas of Sri Lanka that are rarely hit by tropical storms. The third was late in the season and was about to dump even more rain on already soggy ground in Vietnam and the Philippines.
“You realize it’s like a monster,” Tangan said.
Cyclonic storms caused heavy rains and catastrophic flood – including, in one area, the second wettest day on record – at sites South and Southeast Asia. They killed more than 1,700 people, according to CNN, based on data from emergency management agencies.
Many countries are struggling to recover from the worst flooding in decades. Hundreds of people remain missing, likely swept away by fast-moving floodwaters or buried under thick layers of mud and debris.
The region is accustomed to monsoon rains and frequent flooding, but the terrible loss of life and level of destruction shocked many. Scientists warn that as the climate crisis intensifies, more intense extreme weather events will become the new normal.
“This is a human tragedy. There are many conditions happening at the same time, and that makes it unprecedented,” Tangan said.
Rare storms in unusual places
“Relentless,” “rare” and “record-breaking” are words scientists have used to describe the biblical floods across thousands of miles from Sri Lanka to Indonesia, Malaysia, Thailand, Vietnam and the Philippines.
Experts say the disaster was caused by an extraordinary combination of overlapping, powerful weather systems exacerbated by the man-made climate crisis.
Tropical Storm Senyar formed north of the equator in the Strait of Malacca, the waterway between Indonesia's Sumatra and the Malaysian peninsula – a rare occurrence that may have helped aggravate the disaster because locals were not accustomed to cyclones, Tangang said.
Storms rarely take shape near the equator because the planet's rotation there is too weak to provide the Coriolis force that drives the cyclone.
In another unusual turn, the storm turned 180 degrees and moved south and east, which is highly unusual in this part of the world where the Earth's rotation means storms tend to move west and move north, he added.
Meanwhile, Cyclone Ditwa crept along the east and north coasts of Sri Lanka, dumping huge sheets of rain on the low-lying beach coast and central hill country – an area that also had no experience of dealing with tropical storms.
Rains from Typhoon Coto triggered floods and landslides in the Philippines, which experienced back-to-back deadly typhoons and widespread flooding before moving towards already water-logged Vietnam.
A cold surge a few weeks earlier brought strong winds from the north across the South China Sea, where they collected moisture and dumped it as rain on Thailand and Malaysia.
Already wet region
At the beginning of November two major typhoons carved a path of destruction through the Philippines in less than a week. Fung-wong's trail covered almost the entire archipelago. Kalmaegi killed at least 200 people before hitting Vietnam as one of the strongest typhoons on record.
Communities in central Vietnam have barely recovered from widespread floods and landslides that have killed at least 90 people, inundated historic areas and devastated farmland.
One weather station in central Vietnam recorded a national 24-hour rainfall record of 1,739 millimeters, according to Claire Nullis, a spokeswoman for the World Meteorological Organization.
A woman rows a boat through a flooded street after heavy rains in Hoi An, Vietnam, October 30, 2025. – Nhac Nguyen/AFP/Getty Images
“It's really huge. It's the second-highest known rainfall in the world in 24 hours,” she told a briefing in Geneva.
Like a sponge full of water, the earth could no longer absorb moisture. People lost their homes and livelihoods and faced even greater losses.
Then came Coto, Señar and Ditwa, which “created successive pulses of precipitation that hit already saturated river basins,” said Joseph Basconsillo, a senior weather specialist at the Philippine Atmospheric, Geophysical and Astronomical Services Administration.
“Once the surface became wet, the additional rain quickly turned into severe flooding.”
Severe floods and landslides quickly overwhelmed entire communities, catching many people by surprise.
“The combination of unusual storm tracks and vulnerable landscapes made the impact much more severe,” Basconcillo said.
In addition to this chaotic cocktail, two natural climate events occurred simultaneously that typically bring above-average rainfall to the region: Young woman and negative Indian Ocean Dipole.
La Niña and the negative Indian Ocean Dipole cannot explain the disaster on their own, but they “created a background environment that made intense rainfall more likely,” Basconsillo said. “The worst impacts occurred when this moisture coincided with severe storms and vulnerable terrain.”
In Hat Yai, in Thailand's southern Songkhla province, floodwaters up to eight feet high washed over the streets where resident Wassana Suti lived. described as in “like a tsunami.”
A woman walks among tree trunks stranded on the shore after deadly floods and landslides in Padang, West Sumatra province, Indonesia, November 30, 2025. – Willy Kurniawan/Reuters
In Sumatra, Indonesia, the worst-hit country where at least 883 people have died, rescue teams are still trying to reach villages cut off by washed out roads and collapsed bridges. Abdul Ghani, a resident of Palembayan in West Sumatra, spent days searching for his missing wife, showing her photo to everyone he met. “I hope they find her body, even if it's just a piece of her arm,” he told Reuters news agency.
A thousand miles away, across the Indian Ocean in Sri Lanka, neighborhoods have been leveled as residents continue to search through thick mud and debris for bodies.
“We could only hear a sound like thunder,” Nawaz Nashara from Alawatugoda village in Kandy told Reuters. “The house next to ours collapsed before our eyes. There was no time to warn anyone.”
“Accumulation of catastrophic events”
Southeast and South Asia are among the most vulnerable places on Earth to the impacts of the man-made climate crisis, for which rich, industrialized countries bear much of the historical responsibility.
It's almost warmer in Asia twice as fast as the world average. Warmer ocean temperatures provide more energy for stronger storms, and climate change is leading to more precipitation as warmer air can hold more moisture, which is then squeezed over cities, towns and populated areas.
The researchers say they now see a pattern unfolding: “an accumulation of catastrophic events.”
“What we are seeing in Southeast Asia is a relentless cycle of storms: weeks of heavy rain during the extreme monsoon season, with record-breaking events happening again and again,” Davide Faranda, director of research at the French National Center for Scientific Research, said in a statement. “This cannot be taken as the norm.”
An urgent phase-out of fossil fuels, which produce planet-warming pollutants, is vital to preventing the worst consequences of the climate crisis. But greater investment is also needed to help vulnerable countries adapt to the impacts that are already occurring year after year.
“As climate change increases the intensity of heavy rainfall, investments in stronger warnings, better land use planning, infrastructure upgrades and environmental solutions become necessary,” Basconcillo said.
Other man-made factors have likely exacerbated the disaster, including environmental degradation and rampant deforestation, which is often exacerbated or abetted by official corruption.
In Indonesia, residents and government officials point to decades of deforestation from illegal logging, mining and palm oil plantations in Sumatra that have degraded the landscape, leaving hillsides more prone to floods and landslides. Similarly, in the Philippines, hundreds of thousands of people took to the streets to protest corruption over flood control projects. Meanwhile, Sri Lanka is just beginning to recover from its crisis. worst financial crisis after seven decades there is little money left to finance infrastructure and public health, according to to the World Bank.
Filipinos shout and raise placards during an anti-corruption protest over widespread graft allegations related to government infrastructure projects in Manila, Philippines, November 30, 2025. – Eloise Lopez/Reuters
On COP30 Summit in Brazil last month, world made a new deal this required tripling funds to help countries adapt to increasingly severe climate impacts. But the countries could not agree on a road map away from fossil fuelsand there were no explicit deforestation commitments or promises of funding.
“The science is really clear, the situation is getting worse,” said climate scientist Tangan. “It's time for the world and governments to get serious about not only fixing the climate, but also making sure their own countries are prepared to deal with the impacts of climate change,” he added.
“We don’t want countries to get poorer, people to get poorer and more families to die because of this.”
More rain is forecast for Sumatra and Sri Lanka this week. A new storm is brewing in the eastern Philippines.
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