Sliven climate — normals and trends
Sliven (Bulgaria) has a warm-summer humid continental climate (Dfb) under the Köppen-Geiger classification. Its mean annual temperature is 10.5 °C and it receives 825 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 (21.1 °C on average) and the coldest is January (-0.7 °C). Rainfall peaks in May.
Sliven averages 83 frost days, 10 hot days (≥ 30 °C) and 122 rainy days per year.
Sliven 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 98 to 68 per year over the period.
The hottest day of the period reached 39.3 °C (on 24 July 2007) and the coldest -26.3 °C (on 24 January 1942).
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
SlivenSliven
- coords
- 42.69°, 26.33°
- period
- 1940–2025 · 86 yrs
Mean daily temperature
10.5°C
Average daily high
14.9°C
Average daily low
6.5°C
Annual rainfall
825mm
Sunshine / day
9.4h
Mean relative humidity
76%
Average peak wind
12.5km/h
Seasonal range
21.8°C
Frost days (< 0 °C)
83 d/yr
Hot days (≥ 30 °C)
10 d/yr
Rainy days (≥ 1 mm)
122 d/yr
Annual snowfall
80.0 cm
Average feels-like high
13.6 °C
Average feels-like low
4.5 °C
Average peak gust
32.7 km/h
Tropical nights (≥ 20 °C)
3 d/yr
Solar radiation
14.4 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
39.3 °C
24 July 2007
Coldest day
-26.3 °C
24 January 1942
Wettest day
72 mm
27 October 1941
Windiest day
37.9 km/h
1 January 1971
Strongest gust
112.0 km/h
1 January 1971
Hottest feels-like
40.8 °C
24 July 2007
Coldest feels-like
-31.1 °C
24 January 1942
Snowiest day
26.9 cm
5 February 1998
Sunniest day
14.9 h
27 June 1941
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 | 7.8 °C | +5.2 °C | 23 mm | -31 mm |
| Feb | 2.8 °C | -2.0 °C | 36 mm | -16 mm |
| Mar | 14.3 °C | +5.6 °C | 38 mm | -21 mm |
| Apr | 14.5 °C | 0.0 °C | 64 mm | -16 mm |
| May | 19.2 °C | -0.3 °C | 119 mm | +9 mm |
| Jun | 27.5 °C | +3.9 °C | 51 mm | -54 mm |
| Jul | 31.0 °C | +4.9 °C | 54 mm | -27 mm |
| Aug | 28.5 °C | +2.1 °C | 55 mm | -1 mm |
| Sep | 23.9 °C | +1.7 °C | 28 mm | -20 mm |
| Oct | 14.8 °C | -1.3 °C | 166 mm | +112 mm |
| Nov | 13.4 °C | +3.7 °C | 95 mm | +32 mm |
| Dec | 6.8 °C | +2.3 °C | 33 mm | -32 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 Sliven?
Sliven has a warm-summer humid continental climate (Köppen Dfb). Over 1940-2025, the average annual temperature is 10.5 °C and it receives 825 mm of precipitation per year.
What is the hottest day ever recorded in Sliven?
The hottest day measured in Sliven between 1940 and 2025 was 24 July 2007, reaching 39.3 °C.
What is the coldest day in Sliven?
The coldest day measured in Sliven between 1940 and 2025 was 24 January 1942, at -26.3 °C.
Does it snow in Sliven?
Yes. Sliven gets on average 80.0 cm of snow per year and has around 83 frost days.
Has the climate of Sliven warmed?
Yes: Sliven warmed by +1.9 °C between 1940 and 2025, a statistically significant trend.
What is the wettest day in Sliven?
The wettest day measured in Sliven between 1940 and 2025 was 27 October 1941, with 72 mm of rain in 24 hours.
What was the windiest day in Sliven?
The windiest day measured in Sliven between 1940 and 2025 was 1 January 1971, with winds reaching 37.9 km/h.
What is the warmest month in Sliven?
The warmest month in Sliven is July (21.1 °C on average); the coldest is January (-0.7 °C).
How much does it rain in Sliven?
Sliven receives on average 825 mm of precipitation per year, spread over about 122 rainy days.
Is it sunny in Sliven?
Sliven gets on average 9.4 hours of sunshine per day, roughly 3,431 hours per year over 1940-2025.
What is the biggest single-day snowfall in Sliven?
The heaviest 24-hour snowfall measured in Sliven between 1940 and 2025 was 5 February 1998, with 26.9 cm.
Are there tropical nights in Sliven?
Yes: Sliven has on average 3 tropical nights per year (temperature staying above 20 °C), over 1940-2025.
What was the most extreme apparent temperature in Sliven?
In Sliven, between 1940 and 2025, the highest apparent temperature reached 40.8 °C on 24 July 2007, and the lowest was -31.1 °C on 24 January 1942.
Compare Sliven with another city
Pick a second city: its normals will be set against these, indicator by indicator.
Nearby cities
The climate around Sliven