Thunderstorms and showers are expected on Wednesday afternoon across most of Belgium, sometimes bringing heavy rain and strong gusts, while the south and south-east should be less affected, according to the Royal Meteorological Institute.
Temperatures will range from 22°C in the High Fens to 25°C and 26°C in central areas, with local highs of 27°C, under generally light winds.
In the evening, thunderstorms and showers will still affect the north of the country but should fade quickly overnight, giving way to clearer spells moving in from France.
Night-time lows will fall to 14°C in the Eastern Cantons and 17°C to 19°C elsewhere. Winds will remain light, becoming moderate in the uplands.
On Thursday, a band of rain and thunderstorms is set to move in from France, bringing fairly heavy rain to areas along the border.
The rain will lose intensity as it moves northwards, before broad clear spells develop and bring a calmer, drier afternoon.
However, more cloudy conditions are expected later in the day, along with a new thunderstorm system that could be particularly active.
Temperatures on Thursday will range from 25°C to 26°C in the High Ardennes and along the coast, to 28°C in central Belgium and 29°C or 30°C in the Campine region. Winds will be light to moderate.
Early in the night, thunderstorms will cross Belgium from south to north, sometimes accompanied by hail and strong gusts, before clearer skies and calmer weather return.
Mist may still form, however, and some light rain could linger in the east. Overnight temperatures will settle between 16°C and 18C, with light to moderate winds.
