Belgium Braces for Second Heatwave After Deadliest June

Belgium is facing its second heatwave in less than a month, with temperatures forecast to exceed 32°C starting July 11–12, just days after health authorities confirmed that the country’s June heatwave was the deadliest in over three decades. Emergency physicians are now warning that young people in particular are dangerously underestimating the risks of extreme heat, as the Royal Meteorological Institute (IRM) issued a yellow alert across the country.

Record Excess Deaths in June

Between 18 June and 1 July 2026, Belgium recorded 1,747 excess deaths — a 47.8% increase above normal mortality, according to data from public health institute Sciensano. The deadliest day was Saturday 27 June, with 641 deaths — more than double the daily average of approximately 260. The following day saw 632 fatalities.

Wallonia was hit hardest, with 919 excess deaths (+76%), followed by Flanders with 682 (+31.4%) and Brussels with 159 (+60.9%). Epidemiologist Toon Braeye of Sciensano described it as “the deadliest heatwave of the last 30 years,” noting that the succession of warm nights made this event uniquely dangerous.

Crucially, the heatwave did not spare younger populations. Some 280 excess deaths occurred in people under 65 years old, while residential care centres recorded 498 more deaths than usual.

Emergency System Overwhelmed

The scale of the crisis pushed Belgium’s emergency services to breaking point. Wait times reached 10 minutes for the 112 emergency line and 25 minutes for the 1733 non-urgent medical triage number, as reported by VRT NWS. Health Minister Frank Vandenbroucke has since proposed taking over management of the 1733 line from Interior Minister Bernard Quintin, citing structural failures.

Dr. Laurens Heeren (33), an emergency physician at UZ Leuven, described the situation: “The entire system became saturated: ambulance services, MUG teams, admission capacity and intensive care. The severity of care was extremely high.” He noted that geriatric patients with multiple conditions arrived with all reserves depleted, requiring simultaneous treatments.

Doctors Warn: Youth Does Not Equal Immunity

In an interview with Het Laatste Nieuws, three emergency physicians issued stark warnings as the second heatwave begins.

“Everyone thinks: I’m young, that won’t happen to me,” said Dr. Stefanie Vandervelden (39) of ZAS Antwerpen. She described treating roofers, dock workers and cyclists who pushed themselves during the hottest hours. “We saw people who cycled 160 kilometres during peak heat. Heat stroke can absolutely cause permanent damage.”

Dr. Dries Helsloot (40) of UZ Leuven added that hot weather changes behaviour: “People drink more alcohol, spend more time outside, take more risks. We saw more deaths from intoxications, drownings, violence and accidents. Not everyone dies directly from heat stroke, but heat influences behaviour.”

Cumulative Risk of a Second Heatwave

While the second heatwave is expected to be less intense — with temperatures reaching 32–33°C rather than the 38–40°C of June — doctors warn of a cumulative effect on already weakened individuals.

“A second heatwave can certainly have a cumulative effect,” Dr. Vandervelden explained. “Elderly people with underlying conditions are often already weakened after a first heatwave. For them, a second heatwave can be the push too far.”

Dr. Heeren confirmed that people who were already at their limit need time to recover. “Some people will develop problems more quickly this time,” he said.

Practical Advice and What to Watch For

The physicians offered clear guidance for the days ahead. Early symptoms of heat-related illness include headache, dizziness and nausea — signs that can escalate rapidly to loss of consciousness and coma.

“The difficulty with heat stroke is that symptoms are often vague,” said Dr. Heeren. “People feel generally unwell without specific pain. If you’ve had several hot days and don’t feel well, get checked.”

Dr. Helsloot urged community vigilance: “Look out for each other. We saw many socially isolated elderly people during the first heatwave. Call your parents, check on your neighbours, help people find cool spaces. In the coming days, this is literally a matter of life and death.”

Political Response and Preparedness

The Interministerial Conference on Health met on 8 July and proposed 10 short-term and 9 long-term measures, including better outreach to vulnerable individuals and reinforcement of emergency triage services. The Wallonia-Brussels Federation activated its crisis unit on 9 July.

As Belgium enters this second heatwave, the message from frontline doctors is clear: heat is not merely uncomfortable — it is deadly, and no age group is immune.

What to Watch For

With temperatures remaining elevated through the coming week, and the World Cup final and festival season coinciding with the heat, health authorities are closely monitoring hospital admissions. The effectiveness of the newly proposed emergency measures will be tested in real time as Belgians face another week of extreme temperatures.