Following another heatwave, temperatures will drop below 25°C on Thursday, bringing the current heat warning to an end, the Royal Meteorological Institute (RMI) said on Wednesday. The yellow warning for drought is also still in place.
Belgium officially entered its second nationwide heatwave of the year on Tuesday, Belga News Agency reports. The RMI uses the term 'heatwave' at the national level when maximum temperatures in Uccle reach 25°C for at least five consecutive days, including at least three days with temperatures exceeding 30°C.
These high temperatures have led to a deterioration in air quality. Ozone concentrations exceeding the European information threshold were recorded on Monday at five monitoring stations in Flanders and Brussels. A new warning phase – the third of the summer – under the "extreme heat and ozone peaks" plan was activated on 25 July.
Belgium was hit by an initial heatwave from 17 to 28 June inclusive, with temperatures peaking at near 40°C. More than 2,000 excess deaths were recorded during this period, according to figures from the Sciensano Institute of Public Health. The national statistics office, Statbel, has clarified that these are provisional figures.
Risk of drought
The various operators and stakeholders involved in water management (Vivaqua and the Port of Brussels) and in prevention, safety and crisis management (safe.brussels) within the Brussels Region decided on Tuesday to maintain the yellow alert level – the drought vigilance phase, according to Belga News Agency.
This means that authorities have implemented certain measures. The Regional Drought Unit, which brings together these key stakeholders, recommends that everyone avoid non-essential water uses. This includes washing cars, filling swimming pools, non-essential cleaning of surfaces (pavements, terraces, etc.), or watering lawns and plants.
In activating the yellow alert, the unit considered several indicators, including rainfall. The situation in the Brussels Region is gradually approaching 'dry' conditions, according to the RMI.
The low water level and drought code yellow at the Brussels-Charleroi Canal in the port of Brussels, Wednesday 29 July 2026. Credit: Belga / Marius Burgelman
Water supply by Vivaqua is operating normally. However, the prolonged drought and successive heatwaves are increasing pressure on water availability. In this context, the flow rate of the Meuse river, which determines drinking water production at the Tailfer site, is "a major cause for concern", Brussels Environment stated in a press release.
The levels of various aquifers continue to fall, but remain good compared with annual averages thanks to winter rainfall.
Furthermore, field observations by Brussels Environment and the assessment carried out by the Flemish Agency for Nature and Forests for the province of Flemish Brabant show that the current risk of forest and green space fires is very high (orange alert). Monitoring on the ground has been stepped up.
The regional drought task force will next meet on 17 August.
