September in Brussels typically marks a transition from summer to autumn. Expect average high temperatures around 18-20C (64-68F), gradually decreasing throughout the month. Average lows hover between 10-12C (50-54F). Rainfall is common, occurring on approximately half the days of the month, but usually in moderate amounts. Sunshine hours diminish compared to the summer months, averaging around 5-6 hours per day.
Understanding the typical climatic conditions during this period is crucial for planning a visit. Packing layers is recommended to accommodate fluctuating temperatures and potential rain showers. This information allows travelers to prepare adequately for outdoor activities, sightseeing, and comfortable exploration of the city’s cultural attractions. Historically, September has offered a pleasant balance between fewer crowds compared to the peak summer season and relatively mild weather, making it an attractive time for tourism.