Most of Belgium placed under yellow heat alert until Sunday midnight
Updated: 28 June 2026, 12:00 UTC | Brussels. Belgium’s Royal Meteorological Institute placed nearly the whole country under a yellow heat alert from Wednesday 17 June at midnight until Sunday 21 June at midnight, BX1 reported, citing an RMI statement. The coast was the exception, with the yellow alert applying there only on Thursday and Friday. The alert covered a spell of high temperatures across much of Belgique, with BX1 reporting RMI forecasts of 32°C or slightly higher in several lowland regions from the centre to the east on Thursday, followed by 33°C to 35°C in many places on Friday. Weekend conditions were forecast to remain mostly sunny, with a risk of afternoon thunderstorms and maximum temperatures between 22°C and 32°C on Saturday and 25°C and 32°C on Sunday. The heat alert followed the activation of Belgium’s “strong heat and ozone peaks” warning phase, which BX1 reported on 15 June, citing the Interregional Environment Cell, CELINE. CELINE said the warning phase was triggered on the basis of RMI temperature forecasts and aimed to alert the public and health professionals to risks for vulnerable people. CELINE also said ozone concentrations were expected to rise gradually, while no exceedance of the European information threshold was forecast at that point. The episode sat inside a broader European heat spell. The Guardian reported on 26 June that several European countries were facing severe heat disruption, while Le Monde reported on 24 June that heat warnings and temperature records were affecting countries including France, Spain, Italy, the United Kingdom and Germany. For residents, the immediate advice remained practical: limit exposure during the hottest hours, drink water regularly, check on older people and people with health conditions, and follow official updates from the RMI and regional health authorities.
Yellow heat alerts do not mean an exceptional emergency, but they signal conditions that require attention. Heat raises risks for older people, infants, outdoor workers, people with chronic illness and anyone exercising or travelling during peak afternoon temperatures.
The subject is ’s national weather-warning system during a June heat episode. The named entities are the , which issues weather warnings; , the that monitors air quality and heat-ozone alert phases; and Belgian residents exposed to high daytime temperatures.
Background
uses colour-coded warnings to flag weather risks before they become acute. Heat alerts are increasingly paired with health and ozone monitoring because high temperatures can strain vulnerable people and worsen air-quality conditions.
Impact
Regional — The warning applied to almost all of Belgium, with a shorter alert period at the coast. Brussels and inland lowland regions were exposed to the highest forecast values, according to BX1’s report of RMI forecasts.
Local — In Brussels and other urban areas, high temperatures increase discomfort in dense neighbourhoods, on public transport and in poorly ventilated housing.
International — The Belgian heat alert coincided with a wider European heat episode reported by international media, with warnings and disruption in several neighbouring countries.
What it means for you
Drink water regularly, avoid strenuous activity during the hottest hours, keep living spaces cool where possible, check on vulnerable people and follow official RMI and health-authority updates.
Opposing perspectives
- Meteorological and public-health authorities
The RMI and CELINE frame the alert as a preventive warning. Their priority is early public information, especially for vulnerable people and health professionals, before heat stress or ozone exposure becomes more serious.
- Outdoor workers, event organisers and commuters
People who must travel, work outside or manage public gatherings face the practical burden of changing schedules, providing shade and water, and monitoring participants without treating a yellow alert as a full emergency shutdown.
Who, where and what
Key people, places and terms in this story
The Royal Meteorological Institute is Belgium’s official weather service and national forecaster. It matters as the authority issuing and explaining Belgian weather warnings, including heat and thunderstorm alerts.
country placed mostly under a yellow heat alert
location named in the update dateline and exposed to high forecast values
country affected by heat warnings and temperature records
country affected by heat warnings and temperature records
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country placed mostly under a yellow heat alert
location named in the update dateline and exposed to high forecast values
country affected by heat warnings and temperature records
country affected by heat warnings and temperature records
area affected by high temperatures
country affected by heat warnings and temperature records
country affected by heat warnings and temperature records
country affected by heat warnings and temperature records
The Royal Meteorological Institute is Belgium’s official weather service and national forecaster. It matters as the authority issuing and explaining Belgian weather warnings, including heat and thunderstorm alerts.
issues weather warnings
source of temperature forecasts and official updates
monitors air quality and heat-ozone alert phases
cited as the body linked to CELINE and the warning phase
ozone threshold not forecast to be exceeded
weather warning applied to almost all of Belgium
warning phase activated before the heat alert
reported the heat alert and related forecasts
reported severe heat disruption in several European countries
reported heat warnings and temperature records affecting several countries
Sources & evidence
- View sourceBX1Primaryprimary· bx1.be· 17 June 2026Retrieved 28 June 2026· 107 days agodate verified· Dated
- View sourceBX1corroborating· bx1.be· 15 June 2026Retrieved 28 June 2026· 109 days agodate verified· Dated
- View sourceThe Guardianbackground· theguardian.com· 26 June 2026Retrieved 28 June 2026· 98 days agodate verified· Background / context
- View sourceLe Mondebackground· lemonde.fr· 24 June 2026Retrieved 28 June 2026· 100 days agodate verified· Background / context
Related to this story
Live connections from the Belgium Impulse ecosystem — not recommendations.
This briefing was prepared with AI assistance and reviewed by a Belgium Impulse editor before publication. methodology.