(LONDON) — More than 2,700 people are estimated to have died in England and Wales in recent months as a result of heat-related causes, a new report has found.
The excess deaths occurred as a result of heat waves in May and June, according to researchers at the London School of Hygiene & Tropical Medicine (LSHTM), Imperial College London and the Met Office.
Globally, heat is the leading cause of weather-related deaths, according the World Health Organization (WHO).
The heat wave that occurred between May 21 and 29 was likely responsible for around 550 deaths, while the heat wave that occurred from June 18 to 28 was likely responsible for about 2,200 deaths, the analysis found.
Both heat waves broke long-standing temperature records, according to the report.
In the U.K., the temperature threshold for an official heat wave is lower than in much of the U.S.
A heat wave is defined as a period of at least three consecutive days with daily maximum temperatures meeting or exceeding the heat wave temperature threshold, according to the Met Office. The threshold varies by county and ranges from 77 to 82 degrees Fahrenheit.
Across much of the U.S., the temperature threshold is at least three consecutive days with daily maximum temperatures at 90 degrees or greater.
The most heat-related deaths occurred southeast of England, with 549 in total. London saw 453 deaths and the West Midlands reported 368 deaths, researchers said. They suggested that people in areas less frequently exposed to extreme heat may be more vulnerable.
“It is vital that action on adapting Britain’s homes, workplaces, and critical infrastructure to extreme heat outpaces these health risks, especially if we are to protect those most vulnerable to its impacts, such as older people, babies, and children,” Malcolm Mistry, assistant professor in climate and geo-spatial modeling at the LSHTM, said in a statement.
About 42% of heat-related deaths that occurred in the U.K. during those months were exacerbated by human-caused climate change, researchers said.
“Climate change is further boosting the temperature of essentially every heat wave we observe today,” Flavio Lehner, a climate scientist at Cornell University, said in a statement to ABC News. “In other words, had the same weather pattern occurred 50 or 100 years ago, it would have also resulted in a heatwave, but one that was a bit cooler.”
It’s not only daytime high temperatures that are a concern. Heat waves are becoming even more dangerous as overnight low temperatures are still too high for people to recover from the heat stress they experience during the day, according to the WHO.
Western Europe, the region most impacted by the historic heat wave in late June, experienced its hottest June on record last month, according to Copernicus, Europe’s climate change service.
Many June and some all-time records for daily maximum temperature were broken in several countries, according to Copernicus.
France’s nationwide average temperature hit 30 degrees Celsius, or about 86 degrees Fahrenheit, on June 24 — the highest-ever temperature recorded, according to weather officials at Meteo-France, the national weather service. High temperatures in Paris recorded in the triple digits in the days after.
High temperatures also impacted cities like Madrid and Rome, according to Copernicus.
There were more than 5,000 excess deaths in Germany and another 4,700 deaths in France, Belgium, Spain and the Netherlands between June 20 and 28, Reuters reported.
Rising atmospheric and ocean temperatures “reflect a climate system continuing to accumulate heat” that result in increasingly intense heat waves and a persistently warm ocean, Samantha Burgess, strategic lead for climate at the European Center for Medium-Range Weather Forecasts, said in a statement.
“June 2026 underscored how profoundly the climate is changing,” Burgess said. “Western Europe recorded its warmest June on record, and continued record warmth in the global ocean.”
Matthew Glasser and Joe Simonetti contributed to this report.
Copyright © 2026, ABC Audio. All rights reserved.