Stoumont Weather in September

September in Stoumont averages 19°C (66°F) during the day and 10°C (50°F) at night. Quite a bit of rainfall is typical this month, with around 84 mm (3.3 in) on average. An umbrella is a good idea.

Rainfall in Stoumont in September

Past climate data indicates that roughly 17 days will see rain, totalling around 84 mm (3.3 in) for the month. A fairly balanced picture this month, some wet days but nothing too extreme in terms of intensity.

Temperature in Stoumont in September

September in Stoumont brings pleasant temperatures, with highs of 19°C (66°F) and nights around 10°C (50°F). Conditions are often most pleasant around the middle of the day. At 10°C (50°F) overnight, it gets properly cold after dark. On the bright side, cold nights tend to make for excellent sleeping conditions.

Sunshine in Stoumont in September

The area experiences a moderate amount of sunshine, with approximately 160 hours of sunlight expected. This means a decent mix of sun and overcast.

Wind Speed in Stoumont in September

Wind speeds average 4 m/s (8 knots) during September. At this speed, expect moderate winds that can raise dust and move small branches. Since this is an average, some days have gentle light winds while others experience stronger breezes that are quite noticeable.

For Stoumont itself, June, July and August generally stand out with the best circumstances. If you're seeking pleasant, dry and sunny weather somewhere else in the world, our weather planner can help you explore other options.

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For a detailed overview over the year and the best time to visit Belgium, check out our Stoumont's climate page.

Stoumont Temperature in September

Min Temperature 10°C (50°F)  

Max Temperature 19°C (66°F)  

Chance of Rain 56%  

Precipitation 84 mm (3.3 in)  

Rainy days 17 days  

Humidity 88% *  

Windspeed 4 m/s (8 knots) *  

Sunshine 160 hours *  

Percentage Sunshine *  

* Data from: Botrange, Belgium (23 KM, 14 Miles).

Daily Historical Temperatures

50-year average (1976-2025)

Based on our historical records, temperatures in Stoumont typically stay consistent throughout September, with daily highs averaging around 19°C (66°F). Nights are cool, with lows typically ranging from 8°C (46°F) to 11°C (52°F).

Average temperatures in September

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Daily Historical Precipitation

50-year average (1976-2025)

Average daily rainfall for each day of the month based on long-term records.

Average precipitation in September

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Historical weather for Stoumont in September

Browse day-by-day weather records for Stoumont spanning 51 years. Select any month and year to see actual temperatures, rainfall, and conditions recorded on each day.

Historical weather Temperatures Precipitation

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Stoumont historical weather extremes in September

Based on weather observations in Stoumont between 1976 and 2025, these are the recorded extremes during September.

• The warmest day in September was on September 15, 2020, with a maximum of 31°C (88°F).
• On September 25, 2025, Stoumont saw its coldest September day with temperatures maxing out at 7°C (45°F).
• The coldest night in September in Stoumont was on September 28, 1987, with a minimum of 1°C (34°F).

What to Wear in Stoumont in September

For Stoumont in September, you'll want flexible clothing. It's wise to pack cotton shirts, comfortable shorts, and a pair of jeans for cooler evenings. A light sweater or jacket is useful for air-conditioned spaces (like buses) or unexpected cool moments. High rain levels are expected, so pack waterproof gear and an umbrella or poncho. It won't hurt to bring your sunglasses along, as you'll see some sunny periods.

What To Do in Stoumont in September

We rated the following activities from 1 (least suitable) to 10 (best) to do.

Swimming

6/10

Cycling

9/10

Walking

9/10

Camping

4/10

Outdoor sports

9/10

Select a Month

Check the conditions for any month of the year.

• January
• February
• March
• April

• May
• June
• July
• August

• September
• October
• November
• December

For a detailed overview over the year and the best time to visit Belgium, check out our Stoumont's climate page.

More climate data for Stoumont

Temperature Rainfall Sunshine Humidity Wind Speed

See the full Stoumont climate overview or explore weather in Belgium.