Sunday afternoon will be sunny and very warm throughout the country, with highs ranging between 26 and 32 degrees, according to the Royal Meteorological Institute (IRM).
Later in the day, clouds could develop and potentially give rise to isolated but intense thunderstorms.
Carrying over into Sunday evening to Monday morning, the sky may become very cloudy with occasional showers or isolated thunderstorms still a possibility.
Night-time lows will remain unusually high for the season, from 15 or 16 degrees in certain valleys of the Ardennes to 20 or 21 degrees in the large cities.
On Monday, the sky will be a mixture of clear periods and cloudier episodes. The morning will start off dry for most regions, however, cumulus clouds are set to develop throughout the day, leading to showers or sporadically intense thunderstorms, especially towards the east and northeast.
In the west, the tendency for showers will increase slightly later on. A fairly hot climate will stay with highs of 23 or 24 degrees in the Ardennes uplands to 27 or 28 degrees in Kempen.
During Monday night into Tuesday, the unpredictable sky continues with a risk of occasional showers or thunderstorms in some places. It will remain quite mild with lows between 14 and 19 degrees.
