Bytom climate — normals and trends
Bytom (Poland) has a warm-summer humid continental climate (Dfb) under the Köppen-Geiger classification. Its mean annual temperature is 8.6 °C and it receives 751 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 (18.6 °C on average) and the coldest is January (-2.5 °C). Rainfall peaks in July.
Bytom averages 97 frost days, 4 hot days (≥ 30 °C) and 144 rainy days per year.
Bytom has warmed by +2.8 °C between 1940 and 2025, or +0.33 °C per decade. This trend is statistically significant.
The number of frost days there went from about 118 to 76 per year over the period.
The hottest day of the period reached 36.9 °C (on 8 August 2013) and the coldest -28.2 °C (on 12 January 1940).
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
BytomSilesia
- coords
- 50.35°, 18.93°
- period
- 1940–2025 · 86 yrs
Mean daily temperature
8.6°C
Average daily high
12.4°C
Average daily low
4.8°C
Annual rainfall
751mm
Sunshine / day
7.4h
Mean relative humidity
78%
Average peak wind
18.2km/h
Seasonal range
21.1°C
Frost days (< 0 °C)
97 d/yr
Hot days (≥ 30 °C)
4 d/yr
Rainy days (≥ 1 mm)
144 d/yr
Annual snowfall
73.6 cm
Average feels-like high
9.9 °C
Average feels-like low
1.8 °C
Average peak gust
34.4 km/h
Tropical nights (≥ 20 °C)
0 d/yr
Solar radiation
10.8 MJ/m²
Has the climate changed?
One stripe per year, 1940 to 2025
+2.8 °C
since 1940
+0.3 °C per decade · r² = 0.53 · 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
36.9 °C
8 August 2013
Coldest day
-28.2 °C
12 January 1940
Wettest day
59 mm
8 July 1997
Windiest day
51.8 km/h
2 March 1956
Strongest gust
105.8 km/h
19 January 2007
Hottest feels-like
39.3 °C
8 July 1957
Coldest feels-like
-33.8 °C
9 February 1956
Snowiest day
17.9 cm
3 April 1970
Sunniest day
15.7 h
30 June 2019
Normals computed over complete calendar years 1940–2025.
A specific year
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Across the whole year
Month by month
| High | vs. normal | Precipitation | vs. normal | |
|---|---|---|---|---|
| Jan | 5.1 °C | +5.2 °C | 53 mm | +6 mm |
| Feb | 3.9 °C | +2.0 °C | 20 mm | -25 mm |
| Mar | 12.3 °C | +5.3 °C | 48 mm | -0 mm |
| Apr | 16.8 °C | +3.5 °C | 34 mm | -21 mm |
| May | 16.5 °C | -1.7 °C | 74 mm | -3 mm |
| Jun | 24.2 °C | +2.8 °C | 55 mm | -32 mm |
| Jul | 24.4 °C | +1.2 °C | 137 mm | +40 mm |
| Aug | 25.3 °C | +2.2 °C | 34 mm | -46 mm |
| Sep | 20.4 °C | +1.6 °C | 101 mm | +39 mm |
| Oct | 12.5 °C | -0.9 °C | 77 mm | +28 mm |
| Nov | 7.4 °C | +0.7 °C | 75 mm | +21 mm |
| Dec | 4.1 °C | +2.1 °C | 10 mm | -39 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 Bytom?
Bytom has a warm-summer humid continental climate (Köppen Dfb). Over 1940-2025, the average annual temperature is 8.6 °C and it receives 751 mm of precipitation per year.
What is the hottest day ever recorded in Bytom?
The hottest day measured in Bytom between 1940 and 2025 was 8 August 2013, reaching 36.9 °C.
What is the coldest day in Bytom?
The coldest day measured in Bytom between 1940 and 2025 was 12 January 1940, at -28.2 °C.
Does it snow in Bytom?
Yes. Bytom gets on average 73.6 cm of snow per year and has around 97 frost days.
Has the climate of Bytom warmed?
Yes: Bytom warmed by +2.8 °C between 1940 and 2025, a statistically significant trend.
What is the wettest day in Bytom?
The wettest day measured in Bytom between 1940 and 2025 was 8 July 1997, with 59 mm of rain in 24 hours.
What was the windiest day in Bytom?
The windiest day measured in Bytom between 1940 and 2025 was 2 March 1956, with winds reaching 51.8 km/h.
What is the warmest month in Bytom?
The warmest month in Bytom is July (18.6 °C on average); the coldest is January (-2.5 °C).
How much does it rain in Bytom?
Bytom receives on average 751 mm of precipitation per year, spread over about 144 rainy days.
Is it sunny in Bytom?
Bytom gets on average 7.4 hours of sunshine per day, roughly 2,701 hours per year over 1940-2025.
What is the biggest single-day snowfall in Bytom?
The heaviest 24-hour snowfall measured in Bytom between 1940 and 2025 was 3 April 1970, with 17.9 cm.
Are there tropical nights in Bytom?
Almost never: tropical nights (temperature staying above 20 °C) are virtually non-existent in Bytom.
What was the most extreme apparent temperature in Bytom?
In Bytom, between 1940 and 2025, the highest apparent temperature reached 39.3 °C on 8 July 1957, and the lowest was -33.8 °C on 9 February 1956.
Compare Bytom with another city
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Nearby cities
The climate around Bytom