Ho Chi Minh City, Bangkok, and Samut Prakan face the highest heat risks globally according to a 2026 University of Oxford study, as a potential “super El Niño” threatens Southeast Asia with prolonged drought and water shortages through 2027.
Why are Southeast Asian cities most vulnerable to heatwaves?
The University of Oxford report, “A globally comparable framework for heat risk assessment in cities” (2026), identifies Ho Chi Minh City as the world’s highest-risk city. Bangkok and Samut Prakan follow in second and third place. Researchers state this risk isn’t just about temperature; it’s a combination of high humidity and the “urban heat island effect.”
These conditions prevent the human body from releasing heat efficiently. The risk is compounded by rapid urban expansion, high population density, and a large workforce performing outdoor labor. Because these cities are major economic hubs located in low-lying coastal areas, they face a double threat of extreme heat and flooding.
What happens if a “Super El Niño” develops in 2026?
Climate models have detected unusually high sea-surface temperatures in the Pacific Ocean, signaling a possible transition into a super El Niño. According to the research, this phenomenon could push global temperatures to record highs, potentially making 2027 the hottest year on record.
The impacts vary by region:
- Southeast Asia: Thailand, Vietnam, Indonesia, and Papua New Guinea face prolonged drought, reduced rainfall, and threats to food security.
- South America: Increased probability of heavy rainfall and severe flooding.
- Pacific Ocean: More intense typhoons and higher risks of coral bleaching.
How is Thailand preparing for water shortages?
Thailand has already initiated water-management measures. This move follows forecasts suggesting that El Niño’s impact could maintain low-water conditions well into 2027. The government is focusing on drought preparedness to protect agriculture and the wider economy from the expected lack of rainfall.
Comparing the risks: Heat vs. Flood
The Oxford study highlights a specific vulnerability for coastal economic zones.
Frequently Asked Questions
Which city is currently at the highest risk for heat?
According to the 2026 University of Oxford study, Ho Chi Minh City in Vietnam is the highest-risk city globally.
What is a super El Niño?
It is an intensified version of the El Niño phenomenon, characterized by unusually high sea-surface temperatures in the Pacific, leading to more extreme weather globally.
How long will the drought last in Southeast Asia?
Forecasts suggest that low-water conditions driven by El Niño could persist into 2027.
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What measures is your city taking to combat rising urban heat? Share your observations in the comments below.