December 2025 Weather Report: Brussels Hoofdstedelijk Gewest
December 2025 brought relatively mild conditions to Brussels Hoofdstedelijk Gewest, with temperatures hovering close to seasonal norms despite some notable fluctuations throughout the month. The capital region experienced a notably drier December than usual, with precipitation levels significantly below historical averages.
Temperature Overview
The average temperature for December reached 6.0 degrees Celsius, virtually matching the normal value of 6.1 degrees and showing an anomaly of just -0.1 degrees. Sint-Lambrechts-Woluwe recorded the warmest day on December 8th, when temperatures climbed to 14.3 degrees Celsius, providing a brief respite from typical winter conditions. In contrast, Oudergem experienced the coldest conditions on December 26th, dipping to -4.2 degrees Celsius, marking the month's temperature extreme.
Precipitation Patterns
December proved to be significantly drier than normal, with an average total precipitation of just 30.9 millimeters compared to the historical normal of 60.9 millimeters. This represents a 49 percent deficit from expected rainfall amounts. Sint-Lambrechts-Woluwe recorded the wettest single day on December 8th with 11.4 millimeters of precipitation, while Ukkel emerged as the wettest location across the region with a monthly total of 34.0 millimeters.
Sunshine and Notable Features
A bright spot in December was the exceptional sunshine, with 99.4 hours recorded compared to the normal 81.8 hours, representing a 22 percent surplus. This above-average sunshine combined with the dry conditions created relatively pleasant weather for early winter, despite the cold temperatures during the latter part of the month. The combination of lower precipitation and increased sunshine hours made December 2025 a notably drier and sunnier month than typical for Brussels Hoofdstedelijk Gewest.