Nynäshamn climate — normals and trends
Nynäshamn (Sweden) has a warm-summer humid continental climate (Dfb) under the Köppen-Geiger classification. Its mean annual temperature is 6.7 °C and it receives 593 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 (16.7 °C on average) and the coldest is February (-1.9 °C). Rainfall peaks in August.
Nynäshamn averages 95 frost days, 0 hot days (≥ 30 °C) and 120 rainy days per year.
Nynäshamn 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 114 to 76 per year over the period.
The hottest day of the period reached 29.9 °C (on 7 August 1975) and the coldest -21.7 °C (on 10 January 1987).
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
NynäshamnStockholm County
- coords
- 58.90°, 17.95°
- period
- 1940–2025 · 86 yrs
Mean daily temperature
6.7°C
Average daily high
8.7°C
Average daily low
4.7°C
Annual rainfall
593mm
Sunshine / day
8.0h
Mean relative humidity
81%
Average peak wind
23.6km/h
Seasonal range
18.6°C
Frost days (< 0 °C)
95 d/yr
Hot days (≥ 30 °C)
0 d/yr
Rainy days (≥ 1 mm)
120 d/yr
Annual snowfall
81.9 cm
Average feels-like high
5.2 °C
Average feels-like low
0.7 °C
Average peak gust
38.7 km/h
Tropical nights (≥ 20 °C)
0 d/yr
Solar radiation
10.2 MJ/m²
Has the climate changed?
One stripe per year, 1940 to 2025
+1.9 °C
since 1940
+0.2 °C per decade · r² = 0.32 · 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
29.9 °C
7 August 1975
Coldest day
-21.7 °C
10 January 1987
Wettest day
64 mm
24 July 1985
Windiest day
67.4 km/h
13 January 1984
Strongest gust
108.4 km/h
13 January 1984
Hottest feels-like
31.2 °C
7 August 1975
Coldest feels-like
-30.3 °C
10 January 1987
Snowiest day
19.3 cm
6 December 1985
Sunniest day
17.8 h
25 June 2024
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 | 2.4 °C | +2.3 °C | 69 mm | +22 mm |
| Feb | 1.3 °C | +1.5 °C | 8 mm | -28 mm |
| Mar | 6.0 °C | +3.7 °C | 8 mm | -24 mm |
| Apr | 9.2 °C | +2.9 °C | 13 mm | -23 mm |
| May | 11.2 °C | +0.2 °C | 31 mm | -6 mm |
| Jun | 16.6 °C | +0.6 °C | 56 mm | +6 mm |
| Jul | 20.5 °C | +1.5 °C | 87 mm | +28 mm |
| Aug | 18.5 °C | -0.1 °C | 57 mm | -9 mm |
| Sep | 16.9 °C | +2.2 °C | 74 mm | +16 mm |
| Oct | 10.9 °C | +1.4 °C | 66 mm | +9 mm |
| Nov | 6.1 °C | +1.3 °C | 47 mm | -14 mm |
| Dec | 5.2 °C | +3.2 °C | 50 mm | -6 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 Nynäshamn?
Nynäshamn has a warm-summer humid continental climate (Köppen Dfb). Over 1940-2025, the average annual temperature is 6.7 °C and it receives 593 mm of precipitation per year.
What is the hottest day ever recorded in Nynäshamn?
The hottest day measured in Nynäshamn between 1940 and 2025 was 7 August 1975, reaching 29.9 °C.
What is the coldest day in Nynäshamn?
The coldest day measured in Nynäshamn between 1940 and 2025 was 10 January 1987, at -21.7 °C.
Does it snow in Nynäshamn?
Yes. Nynäshamn gets on average 81.9 cm of snow per year and has around 95 frost days.
Has the climate of Nynäshamn warmed?
Yes: Nynäshamn warmed by +1.9 °C between 1940 and 2025, a statistically significant trend.
What is the wettest day in Nynäshamn?
The wettest day measured in Nynäshamn between 1940 and 2025 was 24 July 1985, with 64 mm of rain in 24 hours.
What was the windiest day in Nynäshamn?
The windiest day measured in Nynäshamn between 1940 and 2025 was 13 January 1984, with winds reaching 67.4 km/h.
What is the warmest month in Nynäshamn?
The warmest month in Nynäshamn is July (16.7 °C on average); the coldest is February (-1.9 °C).
How much does it rain in Nynäshamn?
Nynäshamn receives on average 593 mm of precipitation per year, spread over about 120 rainy days.
Is it sunny in Nynäshamn?
Nynäshamn gets on average 8.0 hours of sunshine per day, roughly 2,920 hours per year over 1940-2025.
What is the biggest single-day snowfall in Nynäshamn?
The heaviest 24-hour snowfall measured in Nynäshamn between 1940 and 2025 was 6 December 1985, with 19.3 cm.
Are there tropical nights in Nynäshamn?
Almost never: tropical nights (temperature staying above 20 °C) are virtually non-existent in Nynäshamn.
What was the most extreme apparent temperature in Nynäshamn?
In Nynäshamn, between 1940 and 2025, the highest apparent temperature reached 31.2 °C on 7 August 1975, and the lowest was -30.3 °C on 10 January 1987.
Compare Nynäshamn with another city
Pick a second city: its normals will be set against these, indicator by indicator.
Nearby cities
The climate around Nynäshamn