Illzach climate — normals and trends
Illzach (France) has a temperate oceanic climate (Cfb) under the Köppen-Geiger classification. Its mean annual temperature is 9.7 °C and it receives 936 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 (18.9 °C on average) and the coldest is January (0.7 °C). Rainfall peaks in May.
Illzach averages 75 frost days, 7 hot days (≥ 30 °C) and 153 rainy days per year.
Illzach has warmed by +2.3 °C between 1940 and 2025, or +0.27 °C per decade. This trend is statistically significant.
The number of frost days there went from about 94 to 56 per year over the period.
The hottest day of the period reached 38.1 °C (on 13 August 2003) and the coldest -25.5 °C (on 14 January 1963).
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
IllzachGrand Est
- coords
- 47.77°, 7.35°
- period
- 1940–2025 · 86 yrs
Mean daily temperature
9.7°C
Average daily high
13.8°C
Average daily low
5.9°C
Annual rainfall
936mm
Sunshine / day
8.3h
Mean relative humidity
78%
Average peak wind
12.5km/h
Seasonal range
18.2°C
Frost days (< 0 °C)
75 d/yr
Hot days (≥ 30 °C)
7 d/yr
Rainy days (≥ 1 mm)
153 d/yr
Annual snowfall
46.6 cm
Average feels-like high
12.1 °C
Average feels-like low
3.8 °C
Average peak gust
31.2 km/h
Tropical nights (≥ 20 °C)
1 d/yr
Solar radiation
12.0 MJ/m²
Has the climate changed?
One stripe per year, 1940 to 2025
+2.3 °C
since 1940
+0.3 °C per decade · r² = 0.52 · 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
38.1 °C
13 August 2003
Coldest day
-25.5 °C
14 January 1963
Wettest day
53 mm
26 September 1987
Windiest day
58.2 km/h
26 December 1999
Strongest gust
140.0 km/h
26 December 1999
Hottest feels-like
39.3 °C
5 July 2015
Coldest feels-like
-30.3 °C
14 January 1963
Snowiest day
22.3 cm
4 March 2006
Sunniest day
15.0 h
16 May 1940
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 | 6.6 °C | +3.2 °C | 113 mm | +37 mm |
| Feb | 7.2 °C | +1.6 °C | 55 mm | -15 mm |
| Mar | 12.6 °C | +2.5 °C | 49 mm | -22 mm |
| Apr | 17.0 °C | +3.0 °C | 64 mm | -10 mm |
| May | 20.0 °C | +1.9 °C | 69 mm | -23 mm |
| Jun | 26.6 °C | +5.0 °C | 80 mm | -5 mm |
| Jul | 24.6 °C | +0.8 °C | 100 mm | +24 mm |
| Aug | 26.1 °C | +2.7 °C | 139 mm | +57 mm |
| Sep | 19.5 °C | -0.2 °C | 140 mm | +68 mm |
| Oct | 14.6 °C | +0.4 °C | 99 mm | +27 mm |
| Nov | 9.6 °C | +1.8 °C | 97 mm | +14 mm |
| Dec | 6.6 °C | +2.3 °C | 24 mm | -57 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 Illzach?
Illzach has a temperate oceanic climate (Köppen Cfb). Over 1940-2025, the average annual temperature is 9.7 °C and it receives 936 mm of precipitation per year.
What is the hottest day ever recorded in Illzach?
The hottest day measured in Illzach between 1940 and 2025 was 13 August 2003, reaching 38.1 °C.
What is the coldest day in Illzach?
The coldest day measured in Illzach between 1940 and 2025 was 14 January 1963, at -25.5 °C.
Does it snow in Illzach?
Yes. Illzach gets on average 46.6 cm of snow per year and has around 75 frost days.
Has the climate of Illzach warmed?
Yes: Illzach warmed by +2.3 °C between 1940 and 2025, a statistically significant trend.
What is the wettest day in Illzach?
The wettest day measured in Illzach between 1940 and 2025 was 26 September 1987, with 53 mm of rain in 24 hours.
What was the windiest day in Illzach?
The windiest day measured in Illzach between 1940 and 2025 was 26 December 1999, with winds reaching 58.2 km/h.
What is the warmest month in Illzach?
The warmest month in Illzach is July (18.9 °C on average); the coldest is January (0.7 °C).
How much does it rain in Illzach?
Illzach receives on average 936 mm of precipitation per year, spread over about 153 rainy days.
Is it sunny in Illzach?
Illzach gets on average 8.3 hours of sunshine per day, roughly 3,030 hours per year over 1940-2025.
What is the biggest single-day snowfall in Illzach?
The heaviest 24-hour snowfall measured in Illzach between 1940 and 2025 was 4 March 2006, with 22.3 cm.
Are there tropical nights in Illzach?
Yes: Illzach has on average 1 tropical nights per year (temperature staying above 20 °C), over 1940-2025.
What was the most extreme apparent temperature in Illzach?
In Illzach, between 1940 and 2025, the highest apparent temperature reached 39.3 °C on 5 July 2015, and the lowest was -30.3 °C on 14 January 1963.
Compare Illzach with another city
Pick a second city: its normals will be set against these, indicator by indicator.
Nearby cities
The climate around Illzach