Silly climate — normals and trends
Silly (Belgium) has a temperate oceanic climate (Cfb) under the Köppen-Geiger classification. Its mean annual temperature is 10.2 °C and it receives 728 mm of precipitation per year.
These figures are normals computed over 86 complete calendar years, from 1940 to 2025, using ERA5 reanalysis data from the Copernicus programme.
The warmest month is July (17.7 °C on average) and the coldest is January (2.9 °C). Rainfall peaks in July.
Silly averages 45 frost days, 3 hot days (≥ 30 °C) and 142 rainy days per year.
Silly has warmed by +1.9 °C between 1940 and 2025, or +0.22 °C per decade. This trend is statistically significant.
The number of frost days there went from about 60 to 30 per year over the period.
The hottest day of the period reached 39.0 °C (on 25 July 2019) and the coldest -21.2 °C (on 6 January 1979).
Data from ERA5 reanalysis (Copernicus Climate Change Service), redistributed under a CC-BY 4.0 licence. Normals are recomputed whenever the archive is updated.
Climate normals · ERA5
SillyWallonia
- coords
- 50.65°, 3.92°
- period
- 1940–2025 · 86 yrs
Mean daily temperature
10.2°C
Average daily high
13.6°C
Average daily low
6.9°C
Annual rainfall
728mm
Sunshine / day
7.6h
Mean relative humidity
80%
Average peak wind
19.6km/h
Seasonal range
14.8°C
Frost days (< 0 °C)
45 d/yr
Hot days (≥ 30 °C)
3 d/yr
Rainy days (≥ 1 mm)
142 d/yr
Annual snowfall
16.9 cm
Average feels-like high
11.1 °C
Average feels-like low
4.1 °C
Average peak gust
38.3 km/h
Tropical nights (≥ 20 °C)
1 d/yr
Solar radiation
10.8 MJ/m²
Has the climate changed?
One stripe per year, 1940 to 2025
+1.9 °C
since 1940
+0.2 °C per decade · r² = 0.44 · p = < 0.001
Trend fitted by linear regression (ordinary least squares) on annual means. A trend is shown only when it is statistically significant (p < 0.05).
A climograph overlays rainfall (bars) and temperature (line): the standard reading in climatology, where you can see at a glance whether the warm season is also the dry one.
Records for the period
Hottest day
39.0 °C
25 July 2019
Coldest day
-21.2 °C
6 January 1979
Wettest day
67 mm
29 August 1996
Windiest day
58.4 km/h
25 January 1990
Strongest gust
124.2 km/h
18 January 2007
Hottest feels-like
40.7 °C
25 July 2019
Coldest feels-like
-26.0 °C
6 January 1979
Snowiest day
11.7 cm
20 February 1957
Sunniest day
15.9 h
25 June 2023
Normals computed over complete calendar years 1940–2025.
A specific year
Pick a year and see how it compares to normal — warmer, drier or more extreme than usual?
Across the whole year
Month by month
| High | vs. normal | Precipitation | vs. normal | |
|---|---|---|---|---|
| Jan | 5.3 °C | +0.3 °C | 146 mm | +86 mm |
| Feb | 7.2 °C | +1.0 °C | 50 mm | -4 mm |
| Mar | 13.0 °C | +3.3 °C | 12 mm | -46 mm |
| Apr | 17.3 °C | +4.0 °C | 19 mm | -35 mm |
| May | 19.5 °C | +2.3 °C | 49 mm | -17 mm |
| Jun | 23.9 °C | +3.9 °C | 47 mm | -17 mm |
| Jul | 24.4 °C | +2.6 °C | 73 mm | +6 mm |
| Aug | 24.4 °C | +2.7 °C | 25 mm | -39 mm |
| Sep | 20.1 °C | +1.2 °C | 42 mm | -13 mm |
| Oct | 14.8 °C | +0.4 °C | 71 mm | +12 mm |
| Nov | 10.6 °C | +1.6 °C | 59 mm | -5 mm |
| Dec | 8.5 °C | +2.5 °C | 30 mm | -34 mm |
The year's extremes
What was the weather like that day?
Your birthday, a wedding, a memorable trip: discover the actual weather for any date since 1940.
Frequently asked questions
What is the climate of Silly?
Silly has a temperate oceanic climate (Köppen Cfb). Over 1940-2025, the average annual temperature is 10.2 °C and it receives 728 mm of precipitation per year.
What is the hottest day ever recorded in Silly?
The hottest day measured in Silly between 1940 and 2025 was 25 July 2019, reaching 39.0 °C.
What is the coldest day in Silly?
The coldest day measured in Silly between 1940 and 2025 was 6 January 1979, at -21.2 °C.
Does it snow in Silly?
Yes. Silly gets on average 16.9 cm of snow per year and has around 45 frost days.
Has the climate of Silly warmed?
Yes: Silly warmed by +1.9 °C between 1940 and 2025, a statistically significant trend.
What is the wettest day in Silly?
The wettest day measured in Silly between 1940 and 2025 was 29 August 1996, with 67 mm of rain in 24 hours.
What was the windiest day in Silly?
The windiest day measured in Silly between 1940 and 2025 was 25 January 1990, with winds reaching 58.4 km/h.
What is the warmest month in Silly?
The warmest month in Silly is July (17.7 °C on average); the coldest is January (2.9 °C).
How much does it rain in Silly?
Silly receives on average 728 mm of precipitation per year, spread over about 142 rainy days.
Is it sunny in Silly?
Silly gets on average 7.6 hours of sunshine per day, roughly 2,774 hours per year over 1940-2025.
What is the biggest single-day snowfall in Silly?
The heaviest 24-hour snowfall measured in Silly between 1940 and 2025 was 20 February 1957, with 11.7 cm.
Are there tropical nights in Silly?
Yes: Silly has on average 1 tropical nights per year (temperature staying above 20 °C), over 1940-2025.
What was the most extreme apparent temperature in Silly?
In Silly, between 1940 and 2025, the highest apparent temperature reached 40.7 °C on 25 July 2019, and the lowest was -26.0 °C on 6 January 1979.
Compare Silly with another city
Pick a second city: its normals will be set against these, indicator by indicator.
Nearby cities
The climate around Silly