Brussels records about 852mm of rain across roughly 135 wet days a year, which is a 37% chance on an average day. August is the wettest month at 79mm (9% of the annual total) and April the driest at 55mm. Local rain type: drizzle. Brussels is genuinely drizzly — carry a compact umbrella or rain jacket every day. Rain can start without warning even on partly cloudy days.
Chance of rain on an average day: 37%
Rainfall climatology for Brussels. The live hour-by-hour answer for today loads at the top of this page from Open-Meteo and refreshes through the day — the figures below describe a typical year, not today.
Last updated: · Live forecast data refreshes hourly.
| Annual rainfall | 852mm |
| Rain days per year | 135 |
| Odds on an average day | 37% |
| Wettest month | August — 79mm over 13 days |
| Driest month | April — 55mm over 9 days |
| Rain type | drizzle |
| Best dry window | Late spring (May-June) offers the longest dry stretches and comfortable temperatures for sightseeing. |
| Worst rain window | November through January brings persistent grey skies and frequent light rain. |
August delivers 44% more rain than April (79mm vs 55mm). That gap is the difference between planning around showers and ignoring them.
No single month holds more than 9% of the annual total, so rain in Brussels is spread through the year — there is no season you can rely on being dry.
Brussels rain is mostly persistent drizzle, where a waterproof shell beats an umbrella.
Rain falls on about 13 days in August against 9 in April — the frequency swing matters more for planning than the millimetre totals.
Climate normals. Use them to judge whether today's live forecast at the top of the page is typical or unusual for the season.
| Month | Rainfall | Rain days | Chance on a given day | Highs |
|---|---|---|---|---|
| January | 73mm | 12 | 40% | 6°C |
| February | 56mm | 9 | 30% | 6°C |
| March | 64mm | 10 | 33% | 8°C |
| April | 55mm | 9 | 30% | 12°C |
| May | 67mm | 11 | 37% | 17°C |
| June | 72mm | 12 | 40% | 21°C |
| July | 74mm | 12 | 40% | 23°C |
| August | 79mm | 13 | 43% | 23°C |
| September | 68mm | 11 | 37% | 21°C |
| October | 74mm | 12 | 40% | 17°C |
| November | 78mm | 13 | 43% | 12°C |
| December | 76mm | 12 | 40% | 8°C |
Rain probability is the chance that at least 0.2mm falls at your location — not how long it rains. For Brussels we combine the hourly probability curve, expected volume in millimetres, and the city's own rainfall record into a single umbrella verdict.
| Factor | Weight | What it measures |
|---|---|---|
| Hourly probability | 40% | Peak and sustained chance of measurable rain across the next 24 hours. |
| Expected volume | 30% | Total millimetres, which separates a passing shower from a genuine soaking. |
| Timing & duration | 20% | When rain starts, when it eases, and the longest continuous dry window. |
| Local rain type | 10% | Drizzle, brief showers, thunderstorms or monsoon — each needs different gear. |
Live hourly values come from Open-Meteo and refresh through the day. Monthly rainfall figures are climate normals, so they describe a typical year rather than a forecast.
Brussels records rain on roughly 135 days a year — about a 37% chance on any given day — totalling around 852mm.
August, with about 79mm over 13 rain days. That is 9% of the entire year's rainfall in a single month.
April is the driest month at 55mm across roughly 9 days. Late spring (May-June) offers the longest dry stretches and comfortable temperatures for sightseeing.
Brussels is genuinely drizzly — carry a compact umbrella or rain jacket every day. Rain can start without warning even on partly cloudy days.
No. Probability is the chance that at least 0.2mm of rain falls at your location at some point in the period. Check the expected millimetres alongside it: 40% with 0.4mm is a passing shower, 40% with 12mm is a soaking.