Question 1

Which months had the most sunshine in Brussels in 2025?

Accepted Answer

August was the sunniest month in Brussels in 2025, recording 336.6 hours of sunshine, followed by June with 289.0 hours and April with 268.8 hours.

Across the full 2025 calendar year, Brussels accumulated 2,203.9 hours of sunshine, averaging about 183.7 hours per month. The brightest stretch ran from spring into late summer: April through August each delivered more than 260 hours, while the dimmest month was January with just 37.8 hours.

The sunniest months also brought the warmest, driest conditions:

- **August 2025:** 336.6 sunshine hours, mean 18.1°C (64.6°F), high of 32.8°C (91.0°F), and only 29.7mm of rain
- **June 2025:** 289.0 sunshine hours, mean 18.8°C (65.8°F), high of 32.3°C (90.1°F)
- **April 2025:** 268.8 sunshine hours, mean 11.5°C (52.7°F), high of 25.0°C (77.0°F)

By contrast, the late-autumn and winter months stayed gloomy, with October, November, and December each managing under 82 hours of sunshine.

For visitors planning around daylight, the data points clearly to late spring and summer in Brussels. The April-to-August window combines abundant sunshine with low rainfall, making it the most reliable period for sightseeing, outdoor dining, and day trips. If you want the brightest possible experience, August 2025 statistics suggest it is the standout month for sun in Brussels.

Question 2

How much rainfall did Brussels receive in 2025?

Accepted Answer

Brussels received approximately 733 mm (28.9 inches) of total rainfall in 2025, spread fairly evenly across the year but with clear wet and dry spells. This works out to an average of about 61 mm (2.4 inches) of precipitation per month.

The wettest month by far was January 2025, with 165.4 mm (6.5 inches) of rain, followed by a notably wet autumn. October brought 103.7 mm (4.1 inches) and November 109.7 mm (4.3 inches), making the meteorological autumn (September–November) the rainiest season in Brussels at 245.7 mm (9.7 inches). At the other extreme, March 2025 was the driest month with just 19.4 mm (0.8 inches), and the spring months (March–May) totaled only 72.2 mm (2.8 inches) combined.

For context, this annual total is typical of Brussels' temperate maritime climate, where rain is frequent but rarely heavy. The numbers show that precipitation in Brussels is concentrated in late autumn and mid-winter, while spring tends to be the driest and most settled stretch. If you are planning a visit, the March–May window in 2025 offered the lowest rainfall, whereas anyone travelling in late autumn should pack waterproof gear, as October and November together delivered more than 200 mm (8 inches) of rain.

Question 3

What were the temperature extremes in Brussels in 2025?

Accepted Answer

Brussels saw its hottest temperature of 2025 reach 35.6°C (96.1°F) on July 1, while the coldest reading fell to -7.0°C (19.4°F) on January 14. That gives Brussels a full annual temperature range of 42.6°C (76.7°F) between its highest daytime peak and lowest overnight low.

Across the whole of 2025, the city's average temperature settled at 11.2°C (52.2°F), reflecting Brussels' temperate maritime climate with relatively mild swings for most of the year. The summer heat was concentrated and brief: there were 8 days with highs of 30°C (86°F) or more, and 41 days that climbed to at least 25°C (77°F).

Winter cold was more persistent than the headline figures suggest. Brussels recorded 54 frost days in 2025, when the overnight minimum dropped below 0°C (32°F), most of them clustered in January and February.

For visitors and residents, these numbers show that Brussels rarely experiences sustained extreme heat — the warmest months of June through August peaked with average daily highs around 24°C (75°F). Genuine heatwave days are the exception rather than the rule. At the other end, the frequent frosts mean that warm layers and frost protection for plants and pipes are worth planning for between December and February. Overall, 2025 confirmed Brussels as a city of moderate, four-season weather punctuated by short bursts of intense summer heat and crisp winter cold.

Question 4

Which months are the windiest in Brussels?

Accepted Answer

September was the windiest month in Brussels in 2025, with average wind speeds of 14.0 km/h (8.7 mph), followed closely by October and December at 13.6 km/h (8.5 mph) each.

Across the full year, Brussels averaged a gentle 11.8 km/h (7.3 mph), reflecting the city's typically mild, breeze-driven climate. Autumn (September to November) was clearly the windiest stretch, averaging 13.5 km/h (8.4 mph), as Atlantic weather systems began rolling across Belgium more frequently. Winter stayed brisk too, with January and February averaging 12.0 km/h (7.5 mph).

The calmest conditions in Brussels came in spring. March was the single quietest month of 2025 at just 8.3 km/h (5.2 mph), and the spring season (March to May) averaged only 10.1 km/h (6.3 mph). Summer was similarly settled, averaging 10.9 km/h (6.8 mph), with July and August among the lighter-wind months at around 10.3–10.4 km/h (6.4–6.5 mph).

For visitors and residents, this means Brussels rarely experiences strong sustained winds, even in its windiest months. If you are planning outdoor activities, cycling, or sightseeing where calmer air is preferable, the spring and summer months from March through August offer the most settled conditions. Those sensitive to gusty, cooler weather should expect the breeziest days during the autumn and early winter stretch from September onward, when wind speeds in Brussels peak for the year.

Question 5

What is the weather like in Brussels in December?

Accepted Answer

Brussels in December is cool, damp, and grey, with mild early-month days giving way to a genuine cold snap before New Year. In December 2025, the city averaged a mean temperature of 5.7°C (42.2°F), making it a typical early-winter month.

Daytime highs in Brussels averaged 8.0°C (46.4°F), while nights cooled to an average low of 3.0°C (37.3°F). The month was a tale of two halves: a mild, wet spell peaked at 14.5°C (58.1°F) on December 7, before a late-month freeze pushed temperatures down to -5.1°C (22.8°F) on December 29. Overnight frost was common, with 8 days dropping below freezing.

Rainfall was moderate but persistent. Brussels recorded 35.9 mm (1.41 in) of total precipitation across the month, with some measurable precipitation falling on 11 of the 31 days. Skies stayed mostly overcast, delivering just 79 hours of sunshine and a high average humidity of 87.3%. Winds were light to moderate, averaging 13.6 km/h (8.4 mph).

For visitors, December in Brussels means packing for damp cold: a waterproof coat, warm layers, and gloves for the frosty final week. The low daylight and frequent grey skies suit indoor attractions, cosy cafés, and the city's Christmas markets, while the late-December freeze can bring crisp, sunny mornings ideal for sightseeing.

Bas Ransbeek

Wallonia

FAQ

Which months had the most sunshine in Brussels in 2025?

How much rainfall did Brussels receive in 2025?

What were the temperature extremes in Brussels in 2025?

Which months are the windiest in Brussels?

What is the weather like in Brussels in December?