Today (Friday), the weather will be warm and sunny across the entire country. This is per the forecast by the Royal Meteorological Institute (RMI).
Maximum temperatures will be around 25°C in coastal areas, between 21°C and 25°C in the Ardennes and around 26°C or 27°C elsewhere.
The wind will become moderate and, at the coast, it may come from the north-east in the afternoon. This will significantly reduce average temperatures.
On Friday evening, and also during the night, the sky will remain clear, with temperatures decreasing to around 12°C in the Hautes-Fagnes (an upland area) to 17°C in low-lying areas.
On Saturday, warm air will spread across the country from a south to south-easterly direction. It will be sunny and temperatures may reach 23°C to 25°C in the Ardennes, 26°C or 27°C at the coast, and 28°C to 30°C elsewhere, with a moderate south to south-westerly wind.
At the end of the afternoon, but also during the evening and throughout the night, some thunderstorms may develop, particularly in the west of the country.
On Sunday, the weather will still be very warm with a more marked risk of showers. Monday is expected to pan out in the same way.
The weather will be variable and still hot with showers, indeed possibly thunderstorms, and maximum temperatures of 29°C. It is expected to be fresher from Tuesday onwards.
The Brussels Times