Humid heat is related to heat stress, occurring when environmental conditions overwhelm the body’s ability to cool itself. Severe heat stress leads to an increase in the core body temperature of 3°C or more and can cause confusion, seizures, and loss of consciousness. If not treated promptly, severe heat stress can lead to muscle damage, major organ failure, and death.

Lead author of the study Dr. Lawrence Jackson, a Research Fellow in the School of Earth and Environment, said, "With climate change driving more frequent and intense humid heat events, particularly in tropical and subtropical regions, the risks to vulnerable populations and outdoor workers are increasing.

Co-author John Marsham, a Professor of Atmospheric Science in the School of Earth and Environment, added, “Our results focus on the daily timescale for these heat waves. An obvious next step would be to extend our analysis to hourly time scales which might allow us to work towards near real-time predictions with all the benefits that it would bring to vulnerable communities.”

The study: https://www.nature.com/articles/s41467-025-58694-6