Figures released by Royal Meteorological Institute (KMI) show that last year was the 4th warmest year in Belgium since records began in 1833. The average temperature at KMI’s Ukkel (Brussels) weather centre in 2025 was 12°C. This is the same as in 2014. Only 2020 and 2022 (both 12.2°C) and 2023 (12.1°C) were warmer.
Following what was the wettest year on record, precipitation fell sharply in 2025. Total rainfall in Ukkel was just 620.6mm. This is only around half of the 2024 rainfall total.
There are also some striking temperature records in the KMI's figures. The first “summer day”, the definition of which is a day when temperatures reach at least 25°C, was recorded as early as 12 April. This is the earliest date on which a “summer day’ has been recorded since KMI started keeping figures on this in 1892.
As well as being one of the warmest years on record, 2025 was also the 4th sunniest year within the current reference period. Sunshine totalled more than 1,804 hours. This compares with a reference period record of 2,021 hours of sunshine that was set in 2003.
Big drop in rainfall
The rainfall figures are particularly striking. Following the exceptionally wet conditions of 2024, 2025 was notably dry. The number of days with precipitation (145) was the second lowest since records began. With 142 days, only 2018 had fewer days of precipitation. Snow fell on just 7 days in Ukkel. This compares to a long-term average of 17 days per annum.
Other striking figures
KMI also reports several other notable weather events in 2025. There were two official heatwaves occurred during the summer. The highest daily rainfall total was measured on 8 September, when 62.0 mm fell in Hockai, near Stavelot (Liège Province).
At 3pm on 2 July there was a difference in temperature of 19.9°C between the West Flemish coastal municipality of Middelkerke (18.1°C) and Diepenbeek in Limburg Province where it was 38.0°C.