‘No Human Can Last Beyond Two Hours’: Scientists Warn India’s Heatwave Nearing Dangerous Wet-Bulb Limits

IMD warns of severe heatwaves across India as experts caution that rising wet-bulb temperatures are nearing dangerous survival limits.

High wet-bulb temperatures near 33°C are dangerous and can become unsurvivable with prolonged exposure

Source : Special arrangement

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Key points generated by AI, verified by newsroom

• India faces severe heatwave conditions; relief expected after May 29.
• Portuguese analyst warns of lethal heat and humidity combinations.
• Wet-bulb temperature measures heat danger; higher levels are life-threatening.
• Heatwave frequency and intensity are increasingly alarming.

India is bracing for several more days of punishing heat as the India Meteorological Department (IMD) warned that severe heatwave conditions are likely to persist across northern, central, and eastern parts of the country before temperatures begin easing later this week. According to the IMD, northwestern and central India are expected to remain under intense heat stress for the next three to four days, while eastern and adjoining peninsular regions could continue to face extreme conditions for another two to three days. Relief is expected only after May 29, when maximum temperatures are forecast to decline across many affected regions.

States including Punjab, Haryana, Delhi, Uttar Pradesh, Rajasthan, Madhya Pradesh, and Vidarbha remain among the worst-hit areas, with temperatures hovering in the mid-40s Celsius. The weather agency has also warned of hot and humid conditions in coastal and southern regions, including Tamil Nadu, Puducherry, Karaikal, Konkan, Goa, and parts of Gujarat.

Portuguese Climate Analyst Warns Of “Lethal” Wet-Bulb Conditions

Portuguese climate analyst Bruno Brezenski issued a stark warning about the dangerous combination of heat and humidity now emerging across parts of India. Brezenski noted that locations experiencing “feels-like” temperatures of nearly 55°C could simultaneously record wet-bulb temperatures approaching 33°C, dangerously close to the threshold scientists consider unsurvivable for prolonged exposure.

He warned, “At that threshold, no human can last beyond two hours, and vulnerable groups such as infants and the elderly may collapse within half an hour.”

'This is the chaos most geopolitical analysts aren't factoring into their takes on the shifting global order. I do, because it's the main driver—we're talking full-on global civilizational collapse, way bigger than the US's desperate antics over its hegemonic decline," he added. 

The analyst cautioned that rising global temperatures could push India toward repeated lethal heat events in the coming decades, potentially triggering mass migration and large-scale disruption by 2050.

Eai, quem disposto a ir pra Índia nos próximos dias? 🇮🇳🥵
Boa parte do país terá sensação térmica acima de 50°C, alguns pontos chegando nos 55°C.

Pensa na loucura.🫠

Detalhe, essa região que atingirá a sensação de 55°C, significa também que vai atingir 33°C do bulbo úmido.… pic.twitter.com/xeqPclxpGb

— Bruno Brezenski (@bbbrezenski) May 24, 2026

What Is Wet-Bulb Temperature?

Wet-bulb temperature is considered one of the most accurate indicators of how dangerous heat conditions are for humans because it combines air temperature with humidity levels. Unlike regular temperature readings, wet-bulb measurements assess whether sweat can effectively evaporate from the body and cool it down. High humidity limits evaporation, meaning the human body struggles to release heat even if people remain hydrated.

A wet-bulb temperature near 35°C is widely regarded as life-threatening because the body can no longer cool itself adequately, increasing the risk of hyperthermia and heat stroke.

Scientists measure wet-bulb temperature using a thermometer wrapped in a wet cloth and exposed to airflow, simulating the cooling effect of evaporation. The closer the wet-bulb reading is to the actual air temperature, the more humid and dangerous conditions become.

Research published in Science Advances in 2020 found that humans cannot survive prolonged exposure to wet-bulb temperatures of 35°C. NASA Jet Propulsion Laboratory researcher Colin Raymond explained that once wet-bulb temperatures approach body temperature, sweating becomes ineffective, as quoted by a report.

Prolonged exposure can lead to heat stroke, organ failure, confusion, fainting, coma, and death.

Data from the Indian Institute of Tropical Meteorology indicates that heatwave frequency in India’s core heatwave zone has increased by around 2.5 days every decade since 1961, with the trend accelerating sharply in recent years.

IMD Findings Show Heatwave Risks Intensifying

The IMD’s seasonal forecast for April to June 2026 had already warned that above-normal heatwave days were likely across eastern, central, and northwestern India, as well as parts of the southern peninsula.

An IMD study spanning four decades also found that wet-bulb temperatures along India’s coastline have steadily risen, particularly since the early 2000s. Additional international studies suggest the risks are escalating even faster than previously expected. Researchers at Penn State University found that even healthy young adults begin losing the ability to regulate body temperature at wet-bulb levels near 31°C.

Field reports from coastal regions have further highlighted the growing impact of humid heat. Fishers in Kerala’s Alappuzha reportedly say nights no longer cool down, while labourers in Odisha’s coastal districts describe severe dehydration within an hour of outdoor work.

A 2024 Climate Trends study in Chennai also revealed that indoor nighttime temperatures in several homes remained above 32°C and occasionally crossed 35°C, highlighting how dangerous heat stress is increasingly extending into urban living spaces.