Tuesday will remain dry until the afternoon when rain and thunderstorms will move into Belgium from the French border, the RMI reports.
The whole day will be very hot, with temperatures only cooling down during the night.
The Royal Meteorological Institute of Belgium (RMI) has issued a code yellow warning for thunderstorms across the country, from 14:00 on Tuesday to 02:00 on Wednesday.
The thunderstorms will possibly be strong locally and include hail, heavy wind gusts and a lot of rain in a short period of time. It will be very warm during the day, with maximum temperatures of 25°C at the sea and in the High Fens and 30°C in the Kempen region. Only in the course of the night will the rains calm down and temperatures cool to between 14 to 19°C.
The rains could exceed 20 millimetres in an hour in localised areas and, combined with Monday night’s rainfall, could top 25 millimetres in 24 hours – between midnight on Tuesday and midnight on Wednesday.
Local values could be as high as 40 or 50 millimetres in 24 hours, RMI forecasts.
On Wednesday it will remain mostly dry and the sun will be back, with the temperature then fluctuating between 22°C by the sea and 27°C in the centre of the country.
On Thursday, the RMI again warned of heavy rain and severe thunderstorms, although in the west of the country it should remain mostly dry and sunny. Temperatures will then range between 17 and 24°C, depending on where most of the precipitation falls.